Stef and Lena hesitate to give their blessing when Mariana's biological grandfather tells her she must be baptized in order to be her new half-sister Isabella's godmother. Callie's actions at her birthday party are called out by Stef, and they make a big decision in order to avoid jeopardizing her adoption.

The family visit Brandon to attend his music competition, and secrets surface during the trip. Meanwhile, Callie questions Carmen and Brooke's motives; and Mike observes something that may bolster Stef's theory about the hit-and-run accident.