Mariana worries Nick will break up with her after Zoe reveals that she cheated on Mat when they dated. Meanwhile, Callie serves as a character witness for a friend trying to regain custody of her daughter; and the twins try to help their birth father.

A tragic loss leads Callie to make a shocking discovery, putting her in a moral dilemma; and a gift from Nick causes Mariana to feel more guilty about her and Mat. Meanwhile, Brandon reveals to his moms that Cortney has a child.