After breaking up with her commitment-phobic boyfriend, Billie has a fling with a younger guy, ends up pregnant and decides to keep the baby – and the daddy.

While snooping through Zack's belongings Billie discovers a note addressed to her, that he never finished writing and sets out to find what Zack is hiding.

Billie and Zack have their first big argument after Zack tries to surprise Billie by installing a low flow toilet.

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.