He meets Ian and asks him for directions since he has come to help with the new homeless shelter. He spots the head Frank Gallagher and is surprised to hear that he is Ian's father.
Sometime later, he and Ian hang out a bar where Ian learns Trevor is transgender and this causes mild tension but they reconcile. The two soon get closer and he comes to see the dysfunction of the Gallagher Family and is amused by it.
He also tells Frank that he should be lucky that the homeless only threw him out after the latter protests about not being let back in his home. He watches Ian pepper spray his father and is surprised by the Gallagher lifestyle. He soon witnesses Frank take Liam to school as another way at making amends with his son.
Trevor also helps Ian forgive his mother Monica Gallagher after she returns and he gets to know her.
He and Ian hit a rough patch when Ian ignores his calls and reconciles with a recently-escaped Mickey Milkovich.
Trevor tells Ian that he will go with him to Monica's funeral but after that he won't associate with him again. Trevor watches as Frank speaks up for Monica by making a touching statement and leaving.
Trevor seems like he could not forget about Ian, and vice versa. He seems to be dating someone else, but one of his friends comments on Ian and says that, "You let him go because he f**ked an old boyfriend?" Ian also comments on Trevor while talking with Rita.
As of the eighth season, Trevor reveals to Ian that when he is upset he goes to a "chub" bar to hook up with larger men. He admits that he had been there most recently because he had been upset about Ian's brief resurrected relationship with Mickey Milkovich.