In We Built This City, After when Peter's mom, Daphne tells him that they're moving to Regina to take care of his sick grandmother, Peter meets up with his dad and step-mom, who happens to be pregnant with Angel at the time, at the Dot. Peter tells his dad that he wants to move in with them but Troy tells him that there won't be any more left with the baby coming so they're forced to say no.
In Heat of the Moment, Troy drops by Peter's loft unannounced and asks Peter to watch Angel, which forces Peter to cancel his band practice that was going on. Peter expresses his dislike of her to his girlfriend, Mia, though she tells him to give her a chance. During the times that Peter would babysit, Angel would mostly cry. However, when Troy tries to push his assistant to watch Angel, Peter volunteers to watch her because he recalls what it felt like being neglected by his father as a child. Peter makes Troy promise to be a better father to Angel than he was to him.
Even though Angel only appeared in one episode, it is assumed that Peter keeps checking on her.