Plot summary
Pete's work is turned upside down when Adam brings their mother to St. Ambrose. After examining his mother, Pete finds out that Adam got their mother out of jail by poisoning her. Violet and Sheldon work on the case of a teen pregnancy pact, but things get complicated when the mother of one of the teens bought Violet's book and refuses to let her daughter be treated by Violet anymore. Cooper and Amelia fight over what procedure a piano protegé should receive, one that could save his life but leave him unable to play the piano ever again.
Violet finds out that Sheldon has been dating Marla Tompkins, the reviewer that bashed her. Marla gets angry at Sheldon when she believes that he is putting Violet ahead of her. Charlotte is shocked to find out that Cooper had played the piano, and gets him to show that he shouldn't ever give up his dreams. Pete decides to forgive his mother for all of the horrible things that happened. His mother dies after the poisoning ruined her heart.
Credits
Adapted from Wikipedia contributors, Private Practice season 4. HTML formatting and reference markers removed.