Carl is seen as the trouble maker in Season 1, after almost facing expulsion. In Season 2, his love for selling drugs starts when his grandmother Peggy convinced him to get prescription drugs to make meth. Carl’s delinquent side is somewhat on hold in Season 3, but he does end up shaving his head due to Frank convincing him he has cancer. We see Carl's first love interest, Bonnie, in Season 4, but their relationship ends when Bonnie disappears with her family to an unknown fate.
Carl's interests include drinking, weapons, explosives, and death. Carl does seem to actually be a relatively good child, however he is heavily affected by a completely dysfunctional childhood and family. Nonetheless, he cares deeply about his family, including his father Frank, despite the latter’s complete and utter failure as a parent and role model. In his adolescence, he detaches from Frank though he continues to love and show concern for him at times even when angry with him.
In Season 5, he uses his nephew, Chuckie, to deliver drugs but gets caught when his half-sister Sammi notifies the police. In his trial, Fiona wants him to grovel, but he instead insults the judge and doesn't name his drug dealer, which lands him a year in juvenile prison. He didn't mind as he wanted the experience to boost his reputation. Due to his refusal to snitch, he is accepted by his dealer's gang.
After his release from juvie in Season 6, he adopts a thuggish attitude and believes he is too cool for most things. His new way annoyed his family and friends who told him to stop but he ignored. He also tries to impress his new love interest Dominique Winslow though his ways cause her to rebuff his advances. Once his juvie friend Nick kills someone, Carl is then traumatized by the event and throws away his thug behavior, becoming more like old self though silent. Because of this, Carl ends up gaining the affection of Dominique and forms a relationship with her.
Following Dominique cheating on him, he bonded with her father and decide to better himself by joining military school. Carl became even more serious in his return from school, as seen when he cooked for his family and was respectful to his grandfather Bill Darrgen while taking his suggestion more. Carl has also shown to be afraid of ending up following his families pattern of alcoholism and drug abuse, but also believing that it will catch up with him at some point and that low level jobs are the best he can achieve, though he has also shown determination in trying to rise above this.
Throughout the Seasons
Carl mostly plays a minor role, as he is shown to be a bit of a delinquent and he frequently gets into trouble at school and possibly faces expulsion.
During Killer Carl, he protects his brother Lip from an angry jock who attempted to harm him. Carl struck the bully with a baseball bat and was praised for it by the others.
In It's Time to Kill the Turtle, Carl is excited when Frank gets sober and bonds with his family and friends to pass the time and has fun doing so. Carl is very pleased when Frank does work around the house by cooking and telling stories. However, Lip advised Carl, Fiona, and Debbie to "enjoy the moment while it lasts." Carl doesn't understand Lip's reason and continues to enjoy the sober Frank. Eventually, Frank's soberness becomes too much for the elder children when he tries to break a supporting wall with Carl. He loses his chance at getting the money when Lip and Fiona, spurred by Debbie, force him to drink alcohol. Carl is disappointed since he was enjoying time with his father and doing activities/ When Steve returns to the house, he sees a drunken Frank sitting in his chair holding Liam watching a TV show about politics while the children are pleased.
In Nana Gallagher Had an Affair, Carl watches as Monica takes over as a caretaker for the kids and scrambles at the stress of doing so but is happy to have her. He tries a stunt and builds a ramp, which he rides his bike on and ends up injuring his arm in the process. Carl tells his father who uses this to his advantage by having Carl get struck by a disability investigator and making him think he injured Carl who asks if he can go to the hospital, which Frank promises if he makes it convincing. At the Alibi, he is with Fiona, Lip, and Debbie, as they find their father, he high fives his father over their success. Fiona and Lip inform Frank that Carl got his arm treated and Frank is Liam's biological father. He shares a high five with his father about their scheme. He soon watches as Frank tries to shoo them away. When Frank is criticized and punched, he leaves with his siblings. At dinner, when Lip reveals that that Ian is not Frank's son, Carl is surprised and watches as Ian goes over the test and it reveals that he is the child of one of Frank's brothers, making him both the half-brother and cousin of the family. Carl is surprised that he has uncles while Fiona states he has three.
Carl continues most of his habits and is tended to by his siblings.
In Can I Have a Mother, Carl along with Debbie meets their grandmother, Peggy who comes to visit. Carl is impressed by her having a gun and is pleased to keep her secret after being given money. He later wheelchairs her to the Alibi to find his father and she promises him a drink after refusing to pay him again. At the end, he is sleeping in the old van in the backyard with Frank who was kicked out by Sheila and had his old room taken by Peggy. Carl wakes his father up to tell him that Frank wet the bed, a dismayed Frank told him to scoot over to the dry area.
During A Bottle of Jean Nate, Carl ends up striking a relationship with Peg and has fun with her teaching him to play poker, buys him things from department store, even wants to help him learn a skill... making meth. Frank knew Peg had ulterior motives other than just visiting him and his family, as Peg takes Carl with her to the local drug store to ask people going in if they could buy certain medications for his sick grandma, a young boy being a perfect cover. Despite this, a woman knew what he was obviously doing but complied after he promised her a gram when they are up and running. They get the items they need and head back to the Gallagher house and set up in the basement with their meth making operation. Peg needs to leave and asks Carl to keep an eye on the cooking. He ends up causing an explosion, rocking the entire house. This causes Fiona to keep him away from Peggy.
In Parenthood, Carl is upset about being separated from his grandmother as Fiona scolds him for his act on the house.
Carl is the only Gallagher child loyal to Frank after Debbie sees his ways.
Carl has his head shaved by Frank, who convinced him he had cancer because he wanted to extort the Make a Wish Foundation. Instead, the Foundation sends Carl to cancer camp. Before leaving, Frank gives Carl an unmarked bottle of antacids and tells him they're pills to cure his cancer. Carl hates the camp, as everyone is treated with "kid gloves" and made to participate in wholesome activities. He gets to know another kid and decides to defy the rules set by the camp. A pretty female counselor notices that Carl is unhappy and tries to help him have more fun, but her activities don't live up to Carl's expectations. At night, Carl tries to break into a cabinet with a new friend and another female camper, when the female counselor catches them in the act. Upset that she has failed in her duties as a counselor, she begins crying and asks Carl and his friend how she can make their camp experience more fun. Carl, who still believes he has cancer, tells her he wants to see "real-life boobs" before he dies. The counselor hesitantly lifts her shirt to show the boys her breasts but is caught by the other counselors and ultimately fired. Carl is kicked out of the camp and is sent back to town on a bus with the newly-fired counselor.
Carl also has an unhealthy fixation with death. He attempts to kill his cousin Patrick using rat poison in the middle of the third season after Patrick tries to evict them from the family home. Patrick gets sick, but survives.
Since Carl is still a kid, he has no understanding of sex and sexuality, but has a strange fascination with homosexuality and what exactly it entails. Often in the third season he asks members of his family, and his friend Little Hank about gay sex, simply out of curiosity. Ironically, he and Liam are later placed in a foster home with two gay men interested in adopting them. While staying at the foster home, Carl discovers the couple's gay porn collection and is caught watching it in the couple's bedroom, to which he asks "why do they all have mustaches?'
Carl eventually returns back to the Gallagher home later in season three after Fiona is granted full guardianship of the kids.
Later, in Order Room Service, he attempts to bond with his father Frank, after Frank tells Carl of time when Carl's grandfather and Frank did a heist. They use the security code he was given to break into his "Foster Gays" house with Frank and rob the place. The two celebrate their loot and bask in the glory. After Mickey's wedding, Lip and Ian come home to find a police officer arresting Carl for the crime. Lip tries to defend Carl from the officers but Frank appears on the scene. In a shocking stray from character, he confesses to being the one who committed the crime, by telling them he forced Carl to give him the code and shows items to prove it forcing the police to let Carl go. Carl is tended to by Lip as Frank is arrested, while Carl was amazed by his father's act and watches as he is taken away bidding them goodbye.
After Frank is released but placed in the hospital for his liver in Survival of the Fittest, Carl tends to his father and shaves his head after it is hinted that Frank may have cancer.
During Simple Pleasures, Tony Markovich arrives, Carl is shocked to see that he brought Frank home. Carl tells Tony to put Frank on the bed and bids him farewell after he is done. After Fiona arrives, she immediately wants to kick Frank out when seeing his condition. However, Carl defends his father and tells her he will take care of Frank while intimidating his sister to allow Frank to stay. Fiona begrudgingly allows it and Frank weakly thanks him for his help. In My Oldest Daughter, when Frank's liver fails, Carl takes it on himself to get him pain medication and find him an organ donor. Carl later begs Fiona or Lip to help their father but they don't want to give their liver to Frank, to his sadness. At night, Carl pleads to Fiona who refuses again and apologizes to Carl as he leaves, while Frank tells him and Fiona that he will go to his eldest daughter Samantha for help.
During Like Father, Like Daughter, Carl is going through puberty and flirts with Debbie's new friends who are flattered. He soon helps Frank find Samantha now a grown adult with a kid of her own Chuckie Slott, making Carl remark that he's an uncle. Carl also remarks on his new sister looking like a female Frank and lets Frank go off to talk with her.
As of There's the Rub, Carl breaks his sleeping father's leg at his request to get a check for the liver surgery. Later on, he is syphoning gas from a school bus before he meets with his father and he formally introduces him to Samantha who is excited at meeting part of her extended family and introduces her son to him. Carl is less than pleased to have another older sister but goes along with his father's plan of building a lodge.
Very soon in Iron City, Carl calls Mike Pratt to have him bail out Fiona after she is arrested. He also helps in the search for Frank since he is needed to reclaim Liam or else he'd go into foster care. Carl goes home where he helps Sammi tend to Frank and soon informs the arriving Lip of the new additions to the family, after he inquired on who they are while looking for Frank. He is present with the rest of the family when Liam is released from the hospital. At the end, Carl burns down the sweat lodge his father was in after he is told it nearly killed him.
During A Jailbird, Invalid, Martyr, Cutter, Retard, And Parasitic Twin, Carl is present when Lip takes charge in the house and he agrees with his brother on Sammi needing to earn a keep if she intends to live in the house. Carl also beats up bullies for insulting his little brother's condition. He is also worried about his brother's condition but relieved to see that he is fine.
During Hope Springs Eternal, he is less than pleased when Fiona throws away his taser for her parole officer meeting. He and Debbie decide to go to Sheila's house where they help Sammi tend to Frank. Since Carl also needs a parent to attend his meeting and since Fiona can't go, he decides to take Frank. Carl also helps his half-sister scam people to get money for Frank and is successful in the scheme. He is later present at Lip's college and amazed by the party, as well as Amanda performing sexual acts on Lip. In his school meeting, he takes Sammi along with their father to speak. He watches Frank stick up for him and justifies his attack since he was probably doing them a favor, since they'll most likely be successful. Carl is pleased that his father's rants actually came in handy and he is let off the hook.
In The Legend of Bonnie & Carl, he meets a girl named Bonnie, who lives with her family in a van. They scheme together to gather money for Bonnie's family, and Carl slowly falls for her. He denies this however, when she asks him about it, to which she replies she doesn't want him to love her. Carl goes to the hospital and watches as Sheila marries his comatose father. He prepares to part with his father but is shocked Frank is suddenly rushed out the room, as the doctors explain he is getting a liver transplant since an opening appeared, to Carl's relief.
During Emily, he continues seeing Bonnie and lets her move in along with the family, with Lip giving permission since he wants to scare his girlfriend's parents and they are paid a large sum of money. The next day, Carl goes to see Frank at the hospital and is confused by his father's delirium from his new liver.
After Frank's surgery in Lazarus, Carl goes to see Emily but the van is gone, and so is Bonnie, to Carl's sadness. Carl moves past it and heads to visit his father, where he watches Sheila and Sammi fighting over who should visit Frank. He sneaks in the hospital room, while they are distracted by security and talks with his father, happy to see him okay. Carl then leaves the hospital with Frank who got a new liver. Wheeling Frank out along the Chicago waterfront, he watches as his father takes out a can of beer and victoriously rejoices about surviving and still being able to drink. Frank then shares the beer with Carl to thank him for his help in his time of need. Father and son soon hug at Frank's recovery.
Carl apparently had a skateboard accident prior to the start of the season, likely due to a real-life injury that Ethan Cutkosky sustained prior to filming. Carl initially moves around with the assistance of crutches, but quickly grows tired of them and steals a motorized wheelchair.
In A Night to Remem... Wait, What?, the Gallagher's find out Ian is bipolar. Carl teams up with a gang of drug dealers and spends his time dealing small amounts of drugs for money. Carl later helps his father with getting his money back after he went on a binger. Frank also expressed concern for his son's activities, as he knew Fiona would disapprove. After Frank is left penniless, Carl comforts him and the two share a bottle of booze on the porch.
Carl is eventually given the task of transferring some heroin to Michigan, and seeks advice from Frank about how to do so. Frank warns Carl that he may be easier caught than someone like Chuckie. Carl agrees, and Frank gives him the money to cover the bus fare to Michigan. Carl, having earlier convinced Chuckie to do things for him in exchange for protecting him at school, takes advantage of his nephew's naiveté and straps pounds of heroin to his body using duct tape. Chuckie is not fully aware the bags contain drugs, and agrees to accompany Carl on his trip to Michigan. The pair arrives at the bus station and as Chuckie sits down, Carl spots a security guard with a detection dog and leaves Chuckie behind. The dog begins to bark and Chuckie is caught and arrested.
Sammi later shows up at the Gallagher household and accuses Carl of forcing Chuckie to assist him. Carl repeatedly denies her accusations and eventually, the police show up. Carl's father and siblings tell him to run, to which he bolts out the back door and down the street before getting caught by the police.
Back at the house, Sammi admits she told the police it was Carl, and she also told Chuckie to tell the police that Carl made him do it. Carl is held at the police station several hours for questioning. The next day, Sammi confronts Carl while he is being held and threatens him, to which he replies, "Bring it, bitch." Sammi attacks Carl and punches him repeatedly. In court, Chuckie is sentenced 120 days in juvenile prison, or 60 on good behavior. When asked if Carl regrets his decisions, he simply admits he only regrets trusting Chuckie with the job. The judge is appalled and tells him he will end up in juvie, and follows by asking if that's what he wants. Carl replies, "Yes, please" and humiliates the judge with a vulgar comment. She sentences him to the maximum time of one year in juvenile prison.
Carl arrogantly tells his siblings he intends on making juvie his bitch and is taken away. The finale concludes with Carl and Chuckie on the verge of a gang war.
Carl is released from juvie a few months earlier than expected on good behavior. On his way home he befriended an older boy named Nick, who had been in juvie since he was a child but was released due to his eighteenth birthday. Carl allows Nick to stay at the Gallagher house, much to Fiona's dismay. Carl returns to school and brings Nick along with him. The two smuggle a backpack filled with a cache of weapons into the school and begin running a business selling them. Teachers quickly catch on including the school principal and a math teacher who approach Carl and to his surprise, ask to purchase guns of their own. Carl also takes interest in a classmate, Dominique Winslow.
Carl is not pleased when Chuckie is also released and promises to hurt him, though he never acts on his threat and sees his nephew as foolish in his views.
Carl's attempt to impress Dominique especially when her cop father chases him away. He and Nick soon find a bike which they buy for Nick, as the latter tells Carl how he had a similar bike when he was younger but his father traded it for crack. This also causes Carl to get a bike for Dominique to get around easier, somewhat flattering her.
When the Gallagher's are briefly kicked out of their house, Nick's bike is soon stolen and Carl stops him from going after the person out of disrespect. Carl briefly lifts his spirits by getting him a car. Later Carl, Nick and Debbie are in the car driving to Debbie's baby's gender party, they see a kid on his bike. Nick attempts to reclaim his bike but Carl tells him that it is not worth it. When Nick leaves the party unexpectedly, Carl realizes where he went and follows him. He finds Nick sitting on the kid's porch with a bloody hammer, pondering on his thoughts as crying is heard. Carl walks up to the porch and questions what he did and sees the dead body of the kid with his grieving mother and pukes at the sight in horror. Nick tells Carl he should leave because he called the cops, as Carl questions why he did so but Nick only gives him a look of regret. Carl hears sirens approach. Though reluctant, Carl leaves and watches his friend being taken away. After Nick is taken to prison, Carl decides he no longer wants to be in the drug business. Carl later digs up money and gives it to Fiona and firmly tells his sister to buy back their house with it. Carl is at the house when Fiona reclaims it and is proud.
He is pistol whipped by one of G-Dog's men, when he attempts to stay out of a deal. He goes to Veronica to get stitches, and reluctantly ends up telling her what happened. When Fiona finds out, he tells her about how Nick killed the boy and how "he doesn't want to see that." Carl goes to Frank for help and the latter fills in for Carl in his business and ends up drawing their attention from Carl. Meanwhile, Carl and Sean later confront G-Dog and his men, resulting in the last of Carl's drug days who take their possessions as compensation for his leaving. Carl is given a job at Sean's diner where he washes dishes and earns money in a working way.
He distances himself from Dominique who was used to his attention and he ignores her. When Dominique comes to him for help, he accepts before he is shocked to hear that it was a ploy and she actually likes him. Carl loses his virginity to Dominique, once she comes onto him. Dominique also congratulates him on his job and for being real with her. Things started looking better for him, as he continues to stay away from the drug business and gets a new girlfriend.
He later joins his family and friends in throwing Frank off a bridge after he ruins Fiona's wedding.
As seen in Hiraeth, Carl still dates Dominique, but they do not have a good sex life, as Dominique refuses to perform oral sex on Carl, due to his being uncircumcised. Carl returns home where he, Lip, and Ian are not surprised to see the unconscious Frank who survived the fall. They leave him where he was and Carl asks his brothers if they are circumcised, to which they say yes. Carl checks Liam's penis and sees that even he is circumcised. He makes it a problem and confronts Frank and learns he is circumcised too. Carl bluntly tells his father that everyone kind of hoped he was dead after he had been gone for a month. Like his siblings, he wants nothing to do with him but still has some care for him.
During Swipe, Fuck, Leave, Carl goes to the doctor and gets himself circumcised but it is a painful process for him. He struggles with not getting aroused by his girlfriend who teases him to test his words and it causes him to break a stitch. He gets the problem fixed and the doctor gives him a way to overcome it. He returns home and rests as Fiona comes in asking about his pain and he tells her that he's alright. When she tells she is going upstairs, he told her she can't as he previously found the walls were blocked with cement, courtesy of Frank getting revenge on his children for kicking him out and trying to kill him. Carl was not pleased by his father's act and worked to destroy it. When Lip and Ian teased him for his circumcision, he tells them stop and it already hurt without them making him feel less like a Gallagher. His brothers later give him painkillers, as an apology. After his recovery, Carl sleeps with Dom again.
In Home Sweet Homeless Shelter, Dominique gets gonorrhea and her father Luther Winslow angrily blames Carl but he escapes him. Carl gets a test done to see if he has the disease but sees that he tested negative, meaning he couldn't have gave it to her. Carl finds out from his brothers that Dominique might have contracted the STD with someone else, causing him to suspect her. He follows her and encounters his father along the way, sharing a glare with him. Carl later sees Dominique kissing another man, at a college dorm. He is heartbroken and takes a picture of the act and reclaims the bike he brought her, out of spite. Carl goes to her house and shows the test and the picture to Dominique's father Luther who is shocked by it. To get even, Carl happily tells him her location so that her father could punish her. Afterward, he watches as police storm the dorm and is happy at the sight. Afterwards, he is with his family as Fiona tells everyone they must earn their keep to live in the house. Carl is displeased since his money paid for the house, while Fiona tells him that the house is in her name. Carl is further displeased to see Frank has opened a homeless shelter in an old house and turns his children away for their actions.
As of I Am a Storm, Carl grows a bond with Dominique's father who helps him get into military school by getting a minority scholarship. He is confident in passing the test, since his brother is part black but fails the test. He does another a test, which shows he is part Apache, and Dominique's father is descended from Puritans.
During Own Your Shit , he is jealous to see that Frank's homeless shelter has received new items and remarks to Fiona about their failing house. He is also having second thoughts about school. He later talks with Dominique and she apologizes to him for how their relationship went bad. Carl considers getting back together with her and tells her father that he changed his mind but Luther shows him of how she is still up to no good. Carl meets Dominique's new boyfriend who insults Carl for getting circumcised and she states that the issue doesn't bother her anymore, which causes him to feel betrayed. Carl gets back at both of them by revealing her STD, leaving her boyfriend horrified with her as a smiling Carl walks off.
Soon in The Defenestration of Frank, Carl is preparing for school and is displeased to see Frank return home. Carl insults his father by telling him what Luther is helping with but is angry when Frank tells him about his new luxurious items in his shelter and takes Liam to enjoy them while insulting Carl. The next night, Carl goes to military school and is seen off by most of his family and Luther.
As seen in Requiem For a Slut, Carl does great in the school, as it instills a sense of pride in him and changes his personality for the better. Before long, Carl receives word of his mother's death and decides to go to the funeral, Carl returns home and is greeted with welcome arms. Carl, Debbie, and Liam help their father gather the meth Monica left for them. That night, Carl meets his maternal grandfather Bill Darrgen for the first time and watches as he fights Frank, before Lip tells him who he is. When Bill takes notice of his uniform, Carl explains that he hasn't chosen a branch and is accepting of the latter's compliment to his activities in school and recommends he joins the navy like he did. After his mother's funeral, he and his father go to an alley where Carl graffiti's a wall in honor of Monica. He is shown to have made amends with his father, as they share a beer and pay their respects together before leaving.
After his mother's funeral, Carl has return from military school for the summer. He later finds out his scholarship was given away and he needs to find a new way to pay his tuition.
In Where's My Meth?, he is left with some meth that he sells for more money and buys a hot tub. He is surprised when Frank shows up and tells him he has decided to change his ways and apologizes to Carl for what he has done to him though cannot remember anything. Later, he and Ian are spotted at the unit by a man named Eric Stark who owned some of the meth, forcing the brothers to run.
During God Bless Her Rotting Soul, Eric tracks them and Carl is attacked by him when the thug nearly drowns him in the hot tub as Ian rushes to his aid but is subdued and Eric threatens the family for his money. Carl and his brother research Eric, as he and Ian learn of his dangerous past and decide to ask Lip and Debbie for help but they are unable to get enough money. While the others apologize for not listening to her, Carl does not do so and tells her to stop gloating and help out before Eric comes for her too. After Liam and Frank (who experienced guilt and decided to change) appear to help, Carl and his family are forced to dig up Monica, since Fiona put her share of meth in the ground with her. After digging his mother up, Carl finally admits Fiona was right before they get what's needed. They arrive at the storage unit and pay Eric, Carl offers his hot tub as a way to get more money but its still not enough and Eric threatens them. Fortunately, Frank steps in and Carl watches as he successfully intimidates Eric to accept the payment or be faced with death if he comes near the family again as Carl is surprised by his father's actions and leaves the area with his family.
In Fuck Paying It Forward, Carl and Ian go for a run before they are told of a burglary. Carl gets involved since he heard a veteran was the victim, he promises the veteran that he will catch him. He is shown to still be put off by Frank's change, asking if he's continuing as "Father Frank" but the latter corrects him by stating its "Saint Francis". Carl and Debbie watch as he bonds with Liam before they leave, he and Debbie agree that Frank is still himself though they humor him, since he is showing signs of improvement. At the end, Carl watches as his niece walks to Frank and is happy at this sight and by his father. He soon catches a burglar and chains him in the basement.
Afterwards, Carl starts working odd jobs including working for a knockoff Uber company to earn money. Carl soon handles a robber who was also a drug addict and succeeds in detoxing him. With this, he holds several of them in the basement for days, in hopes that he will get them clean in return for money from their families. It works a couple times but then it starts having problems. He takes in a young girl named Kassidi, and she points out that none of the families of the group he has taken will give him money. He gets discouraged before she tells him she has a plan. She convinces him to send a ransom note to her wealthy father and that way he can get his money. Her father, who knows it's a scam, gives Carl the money hoping that she will come back home. Carl lets her go now that he has the money he needs, but she doesn't want to leave and begs Carl to let her stay with him. She then gives him oral sex and he allows her to stay. Carl and Kassidi start dating and fall in love fast. Kassidi is wild and carefree, similar to Monica. When Carl doesn't hold her hand, Kassidi gets upset though they reconcile after he does the act. After he gets ready for military school, Kassidi doesn't want him to leave but Carl tries to convince her that long distance will work but she is still upset.
To try and show her that he is committed, he buys Kassidi a ring off of a pimp to give her as a promise ring. Carl sets the basement up romantically with candles and leads her down there where he tells her he wants it to be special and takes her to the spot where they fell in love. He then pulls out the ring and Kassidi thinks he is proposing and she says "Yes, I'll marry you." A shocked Carl says "Marry me?" and she says yes again. Carl did not want to upset her and thinks he does love her so he initially believes marriage is okay. Kassidi then wants to get married right away and Carl, who does not want her to lose her mind, agrees. Though they are underage, the couple falsifies documents to show that they are old enough to marry. Carl and Kassidi get married at the courthouse, but the marriage is not legally binding because of their age. They do not invite any of the other Gallagher's because they do not support the marriage.
In order to stop Carl from going to military school, Kassidi handcuffs him to his bed for a day, until he falls asleep. It is implied that Liam releases Carl while sleepwalking. Carl finally realizes that military school is more important to him than Kassidi and sneaks out to buy new supplies for military school.
Carl later boards the bus for military school. Kassidi shows up and begs Carl to come back. Carl ignores Kassidi's pleas and leaves for military school.
In the months that followed in Are You There Shim? It's me, Ian, Carl excelled in military school reaching the rank of Corporal and is more serious. Carl only has one problem being his wife Kassidi who has followed Carl to military school and set up camp outside the fence of the school and supports her husband in his endeavors by dressing up as a cheerleader and cheering him on, to his embarrassment. Carl has gotten over her and is dismayed Kassidi still shows signs of her clinginess to him by counting down the days until he is let out of school and professing her love of him. Carl also learns until she is taken care of, he won't be able to advance to a new rank. When complaining about this to his platoon, one of them who Carl was having problems with decided to help. The cadet later told Carl that he handled it and the body won't be found, implying he killed Kassidi or abducted her to keep her quiet. There was no trace of her at the camp as Carl became worried at the fate of his wife. He later returns home and finds things amiss.
To really advance his military future in Mo White!, Carl gets decides to do community service and get a recommendation. He decides to euthanize dogs but is horrified by the procedure and gets them out for a peaceful death.
Carl later goes to a congressman for help but he has given a recommendation to someone else though with V's help he does get it.
Unfortunately in the next episode, the boy who previously had the recommendation confronts him and challenges him to a duel. Carl goes to a former mercenary for help and becomes scared of the details of a duel but gets enough strength to do so. Carl meets the boy who ends up shooting himself in the leg, to Carl's shock. Carl learns the boy actually wants to be a poet but his strict father wouldn't let him and wanted him to be a soldier. The boy says with his wound, he wouldn't have to go now but Carl says its a flesh wound and it will heal. Hearing this, the boy begs Carl to really shoot him in his other leg, successfully doing so by annoying him with his poetry. Carl is put off by the boy's gratitude but proud of pulling the trigger and leaves as the wounded boy wishes him luck at West Point.
Carl attends a ball for military school and things are good as he meets a girl; the daughter of the officer hosting the event, Kelly Keefe. Kelly comes onto him and they nearly have sex but she passes out. After Kelly wakes up, she accuses him of filming the encounter before chasing him. Carl hides in her father's study, but is found by her father. Carl tells him what happened, but Kelly's dad throws him out. Carl returns home and complains about his venture as Debbie does about her own. However, they stop when Liam's classmate Sissy decides to move in with him. She claims that she and Liam had sex earlier that day and that she is pregnant with his child. Carl, Debbie, and Liam are confused, and Liam is unsure that they even had sex because he does not know what it looks like. Carl and Debbie intervene by telling Liam that he could not have impregnated Sissy. Carl tells Liam to play along until they have a plan. Carl goes outside and buries a dead dog in the backyard. As he finishes burying the dog, Kelly appears and returns his phone that he left behind. Kelly acknowledges that it is not her in the video, and Carl tells her that the girl in the video is actually his ex-girlfriend Kassidi. Carl tells Kelly he did not do anything to her. Kelly apologizes for her misunderstanding and kisses him. Carl is present at Ian's hearing and is pleased when he pleas not guilty by reason of insanity. Later on, he and Debbie have Lip who was told of Liam's situation to help and kick Sissy out by drugging her and bringing her to a clinic.
Carl and Kelly later help with teaching Ian some new moves to help him survive prison. Carl is present at seeing his brother off and wishes him luck.
Carl is woken up at two in the morning, he and his siblings investigate the sound in the attic and see its an alarm with a picture of Ian. They realize that he left them a memento and smile at the gesture.
Carl decides to move in Frank's room since he moved out. He agrees to babysit Liam and Franny before Kelly arrives to help with his lessons but he is disappointed she only wanted to study and has Liam help. While going over military assessments, Carl is informed by Debbie of Fiona's hardships with a car accident and learning of Ford's marriage. A surprised Carl curses Ford and worries about his sister. Later on, he and Kelly keep studying and she is exasperated with Carl's lack of knowledge on the subjects though lets it slip that she wanted a boyfriend with her at West Point. He is later present when Fiona decides to move back in and watching Ford's humiliation and Fiona getting revenge on him by shooting a paint gun at his rear end and takes amusement from the act.
In The Apple Doesn't Fall Far From The Alibi, Carl and Kelly are still seeing each other and fooling around in the tent so her father does not catch them. Later on, Frank asks Carl for help and asks him to masturbate in a cup while promising him a hundred dollars. Carl accepts and does so, having no idea what Frank will do with it.
During BOOOOOOOOOOOONE!, he decides to take up a more assertive stance in sneaking with Kelly but is caught by her father who puts a gun to his head and orders him to leave. At home, Carl soon learns of his father having kids, he scoffs at this while listing himself as an example of his father's failure and calls his fault a military psychopath. Carl later talks with Kelly towards their future by taking Carl to her home. When Kelly forms her own vision board by telling her father and boyfriend that she still wants to go to school and see Carl. He watches as Kelly also abolishes her father's rules and makes a list of demands to him. After ending her rant, she tells Carl that they will have sex in her room and he sheepishly goes along with this.
In Los Diablos, he continues seeing Kelly and makes good with his coworkers though he is angry at being harassed by his old friends who attempt to mug him.
During The Hobo Games, he is congratulated by Kelly on his job and wishes him luck as she and Debbie hang out. Kelly sends Carl a picture and he worries because of their closeness, after his coworkers comment on it.
In You'll Know Bottom When You Hit It, Carl confronts Kelly on her association and she breaks up with Carl for believing she'd be attracted to Debbie and not trusting her.
As of Lost, Carl gets ready for work but finds his father and though tempted to leave him where he is, he decides to help him. Carl along with Debbie and Kelly learn of Frank's leg injury and carry him inside. Carl spends the day at work and is put off by his boss' flirting before he attacks a robber for shooting at him. After work, he finds Debbie and Kelly sleeping on the couch while bemoaning this before going upstairs. At night, he finds his sister crying on the porch and asks what happened. Debbie explains she took the chance to kiss Kelly but the latter rejected her. Carl sympathizes with her over being dumped by Kelly. They reconcile before they spot Kev dressed up as Jesus carrying a large cross.
During Found, Carl and Debbie go out for revenge on Kelly, while telling Fiona they are going out. The two vandalize Kelly's truck and quickly flee the scene when she nearly spots them. Carl later goes to work where the owner thanks him for his acts of saving the restaurant, offering him a promotion and better pay. Carl considers it and tells Debbie that he is quitting school while she tries to protest this but he refuses to change his perspective. He later goes back to work, where he talks with his manager before he notices Kelly's truck and quickly runs away. However, Kelly storms in and tackles him down as she berates him for being willing to throw his life away. Kelly straps Carl's hands to his back as she takes him, while telling Carl's boss that he quits and will go back to school. Carl is loaded up in Kelly's truck and taken away while his manager watches the scene, she comments on how Carl has a real lady keeping him in line.
During We Few, We Lucky Few, We Band of Gallaghers!, Carl graduates from Military School but is forbidden from joining the army because he defended a certain student. Carl is shocked to learn that the student was actually transgender who because of him will now come out unashamed anymore. Regardless, Carl spends his time having wild sex with Kelly before they are forced to get birth control pills after it turns out she was ovulating. Carl is later present for the birth of his new nephew Freddie Gallagher and congratulates his brother.
As of Sleep Well My Prince For Tomorrow You Shall Be King, Carl wakes up and notices Frank in the same bed with Mikey commenting on how their relationship looks weird. Carl returns to his old job at Captain Bob's after previously leaving during season 9. During his time gone, a girl named Anne Gonzalez has started working there as the assistant manager. Carl later caught Anne hiding vapes to sell to underaged kids. The two work out a business deal and Carl becomes attracted to Anne. She looks after him with a smile, clearly taking an interest in him.
In Which America?, Carl and Anne grow closer after Carl poorly helps Anne at her family's tamale business.
In A Little Gallagher Goes A Long Way, Kelly tells Carl that she has syphilis, something he already knew she may have given to him from experience. He and his family have a few close calls with celebrating Ian’s return. Debbie arrives and reveals that Derek’s widow is trying to take her daughter, and Kev and V walk in after. Both times the party anticipated Ian's arrival. Ian soon enters through the back door and asks if there is a scrimmage going on in reference to the decor that Liam procured. Happy to see his brother again, Carl hugs him before they celebrate his return.
In Sparky, Carl comes home with Kelly and Anne where they come in at the argument between Frank and Randy. Carl overhears Frank’s reveal that the babies born from Ingrid are actually his children. Understandably, Carl was very upset with his father for using his sperm to impregnate the woman while Kelly argues with Randy on not leaving the kids with Frank or Carl. However, knowing his father Carl decides to take part in the scam Frank has planned while telling Kelly that Frank is a master with scamming. Holding his new children, Carl talks with Kelly on finding out which one is the best one to keep.
In Adios Gringos, Carl helps Anne and her family get their territory back from rivals and they amass enough money to buy an apartment. Later on, she and Carl bond over cooking before they share a kiss.
During Citizen Carl , Carl witnesses a woman being killed one of the bus stop. Despite the horrific saying nothing is done about it because the story was not important enough. With help from Kelly and her friend Carl is able to stage an elaborate robbing that puts three cameras on the scene of the incident.
In Now Leaving Illinois, Carl is shocked when Lip reveals that he is going to move to Milwaukee with Tami and their son for a better start.
In "Gallavich!", Carl celebrates the union of his brother Ian and Mickey. He later joins Julia at the table before they talk about her sexuality, which she explains is because she was experimenting. Carl then reveals his open mindedness to her kinks, before an intrigued Julia grabs Carl by the arm and invites him to wild sex, which he quickly accepts. The next day, Carl is seen in bed with Julia before the cops show up. Carl and Debbie believe that Frank must of did something and Carl answers the door. However Carl learns that the officers are actually present for Debbie having been called by Julia's mother for statutory rape, something that shocks Carl. Carl soon watches the cops chase Debbie out of the house while Julia questions what is going on. Knowing that he is complicit for the same crime, a worried Carl decides to have a talk with the confused Julia.
- He is one of the few Gallagher children to call Frank "Dad".
- Several times in the early seasons, Frank mistook Carl for Lip.
- Carl is Frank's fifth child and second son.
- After Lip, he is the second Gallagher to have a juvenile record.
- Carl shares similar traits to his father, though Lip is more like Frank.
- He has attempted to kill two of his relatives cousin Patrick and father Frank but both survived and held grudges against him that were soon forgotten.
- Carl seems to notice that all Gallagher's attract unhinged partners.
- He is the third of the Gallagher children to get married, after his sisters Fiona Gallagher and Samantha Slott.
- Similar to them, his marriage lasted briefly with his spouse's disappearance.
- He has her four girlfriends over the series: Bonnie, Dominique, Kassidi, and Kelly.
- Carl is the fourth Gallagher child to have children.
- In Season 11, when his partner asked Carl if he had any kids, Carl simply replied that he was 19. This indicates he's ignoring the illegitimate children that were born from Frank tricking him into donating sperm for Ingrid.
- In season 11, it is hinted that Carl may have impregnated Tish because she did not answer him on if her baby was his. If it is his, Carl will have three children giving him the most out of all his siblings.
- He mentioned in season 10 that he once got syphilis from a girl.
- Carl is the second Gallagher who graduated High School after Lip.
- In Season 10, Carl was worried when Julia's mother had charged Debbie with statutory rape for having sex with the underage Julia, due to the fact that he (technically) is just as guilty of this as well.
- However, in Season 11 Carl was not charged most likely because Claudia had no idea about him.
- He is 33.5% native american, specifically apache.
- Considering that both Frank and Monica must have african DNA to produce Liam and Carl has none, it could be that Frank isn't Carl's biological father; just like Ian.