Terry Milkovich is the father of five sons and one daughter with his wife and an illegitimate daughter with another woman. He is known to have escaped arrest numerous times, which caused Frank to go for him an alibi on suspicion of a crime. He is arguably one of the two main antagonists of season 3.
He very nearly caught Ian and Mickey the first time they slept together, but despite finding them naked together, simply told them to put some clothes on and thought nothing of it, probably assuming they were on drugs. It is later discovered, due to his constant drinking and blackouts he had unknowingly impregnated his daughter Mandy. Around this time Terry had hunted Ian down because he thought he was the father, until Ian and Lip tried to plant an illegal gun in his possession, only the plan back-fired when Terry came home. Terry made a reach for the gun as Ian and Lip began to run. Lip managed to jump out of a window. Ian however, got cornered by Terry in the kitchen only to have Mandy interfere by holding a shot gun to him. As it turned out the father was in fact Terry. The revelation of his impregnating his own daughter disgusted both Ian and Lip.
Additionally, Terry owns more guns and leaves the house unlocked on purpose since, according to Ian, anyone would be crazy to break into the Milkovich's home. He's noted to dislike the older Gallagher boys.
It hasn't been revealed if he was married, or dating the mother of the Milkovich family, who is mentioned being dead during Season 2 in a conversation between Ian and Mandy.
During Father's Day, Frank tries to turn to him when he needed a water-tight alibi to stop the police questioning him about the death of Eddie Jackson. Terry already came up with a perfect story, though charged Frank for it but the latter didn't need it.
It is revealed he has a daughter other than Mandy, Molly, which is revealed when she tries to call him saying her mother has died. Molly is the half-sibling of his other children.
Terry finds out about Mickey's sexual orientation and takes matters into his owns hands to "straighten" Mickey out. He walks in on Ian and Mickey having intercourse and attacks Ian, shouting "Mandy wasn't enough?". Mickey tries to interfere and manages to wrestle Terry away from Ian, but ends up receiving the brunt of Terry's beatings himself. As Ian tries to run, Terry points a gun at Ian and tells him to sit back on the couch. Mickey, barely conscious now, tries kicking Terry off, but Terry hits him with the base of his gun and puts Mickey out. He then calls a Russian girl over to have "corrective" sex with Mickey. When the girl arrives, Terry tells Mickey she is here to "fuck the faggot out" of him. Terry forces Mickey to have sex with her and makes Ian watch. Mickey is seen to be in pain and looks at Ian, but Ian can't return his gaze, emotionally in pain himself. After a short while, Mickey rolls on top of the girl and away from Ian, so that his back is to Ian and he wouldn't see him. He acts like he is suddenly enjoying the sex to get it over with as soon as possible, while Ian watches in dismay.
While the prostitutes are stuck at the Milkovich home for a time duration, Svetlana and the others yell at Mickey while Svetlana adds that he "also has small dick". Terry blames Mickey as well for trying to "liberate" the prostitutes and adds "You do have a small dick" and "This is my house". Terry says it is indeed his (Mickey's) fault because he actually believed the prostitutes deserved more (pay) and thought he could "liberate" them, and says from his (Terry's) experience, she (Svetlana) is not worth anything more.
In Iron City, Terry is seen being hauled from his house by several policemen while yelling profanities at them. He had apparently failed another urine test, thus violating his probation. He is sent back to prison.
In Emily Terry is released to go to the christening of Mickey’s son, and arrives later at the Alibi. He meets his grandson Yevgeny Milkovich and happily holds the child. When Mickey and Ian fight about their relationship and, before Ian leaves, Mickey gather's everyone’s attention to announce that he is gay. Moments later, a furious Terry lunges for Mickey and instigates a bar brawl, with Ian helping and getting revenge on Terry for his previous beating of him. At the end, both Mickey and Terry are apprehended by the police while Terry continues to shout homophobic slurs, and continues his aggression as Mickey provokes him by telling him of sexual activities with Ian. Terry is taken away by the police who criticize him for already breaking probation just four hours after his release, while Mickey is released by a sympathetic gay cop.
It is shown in Do Right, Vote White! that Terry is now out of prison, he is visited by Frank and the latter pays him to help him with getting Mo White back into politics. He gathers old friends and they aid in starting a riot, that ends up getting Mo enough votes to get back into congress.
In Black Haired Ginger, Terry is visited by Ian, while he is annoyed to see him, unlike before he doesn’t attack him and is more patient by telling him where Mickey is. Terry tries to shoo him away but the latter states he wanted to see him. Terry listens as Ian asks him about jail, Terry tells him of his experience there and advises Ian to flee while he had the chance.
During Debbie Might Be a Prostitute, he and some of his relatives are preparing for something before Mickey walks in. Terry tells his son to gear up, before his son reveals he is having issues after his parole officer was killed. Terry asks if he did it but Mickey states he didn't but suspects Ian did and suggest he take the fall but Terry states because of the Milkovich reputation, its a bad idea. After his family suggest, he marry Ian to prevent testifying, Terry rebuffs the idea by voicing his disgust before his niece, Sandy, stated she was gay too.
In Location, Location, Location, Terry has learned of Mickey’s engagement to Ian. Enraged his son disregarded his wishes, Terry runs to the Gallagher house where he shouts out to his son to come out and face him. Mickey comes forward and he and his father argue with Terry threatening him at gunpoint but Mickey isn’t phased in points his gun at Terry. Father and son stare each other down with Mickey refusing to back away from his decision and Terry angrily leaves.
- Similar to Frank, the police are also well aware of who he is, due to his time in jail.
- Terry did 18 years in prison in and out.
- He mentions to having sex with some of the inmates in jail, despite scorning his son's sexuality.
- He is possibly the father of Yevgeny Milkovich, due to also sleeping with Svetlana.
- Despite not being on good terms with his son, he knew Mickey was in Mexico.
- It seems by Season 9, he has gotten over his hatred of Ian but still dislikes him.
- In Season 10, while he still scorns his son's sexuality, he and Mickey have reached neutral ground.