Sometimes, Shameless pulls some real surprises, and “Parenthood” does a good job of it. Not only does Sheila (Joan Cusack) have a hand in Peg’s (Louise Fletcher) death, but Lip (Jeremy Allen White) leaves home when Fiona (Emily Rossum) tells him it’s “school or leave.” She and Lip had made a pact to finish high school, but he gets expelled because of his antics. Mickey Milkovich (Noel Fisher) wants to kill Frank (William H. Macy) after Frank catches Ian (Cameron Monaghan) and Mickey doing the nasty in the Kash and Grab; and Steve/Jimmy (Justin Chatwin) will try anything to get Fiona back.