When Billie and Zack take instructional parenting classes separately due to their schedules, Billie goes with Olivia and Abby. However, the course quickly becomes a competition when Abby outshines Billie at all the tasks.
Worried that she'll ruin Christmas - as she has in previous years - Billie tries to hide from her parents the fact that Zack is living with her. Meanwhile, Abby's husband, Nick, tries to impress their father.
Zack is upset when Billie hires a baby nurse without consulting him. Meanwhile, Davis and Ryan are faced with a difficult choice when they learn surprising news about the nurse.
Billie invites herself to Zack's high school reunion but worries that she can't compete with his hot, ex-girlfriend in her pregnant state. Meanwhile, Olivia helps Abby host a party where they try to sell Abby's miracle youth juice.
Billie unintentionally causes Abby and Nick to break up when she asks them to be Godparents. However, after a fun night on the town with Davis goes too far, Billie must stop Abby before she does something she will regret.
After faking labor pains to get Zack out of a speeding ticket, Billie goes into labor - for real. Unfortunately, things take a turn when Zack gets busted by the officer they had initially lied to and is hauled off to the police station.
Billie's pregnancy creates an attraction from members of the opposite sex, while Billie feels her own results of her hormonal changes, but she becomes really befuddled when Zack rebuffs her advances.
Billie declares that she and Zack are able to see other people, but it's Billie who finds the dating scene a little rougher than expected, and Zack finds a conscience when he tries the waters, too.
