Mikey, now a little bit older, figures he's got it made. His complusive working mother, Mollie wed James, the warm-hearted dad of his dreams. However, his street smart thoughts are soon matched by the irresistible wisecracks of his new baby sister, Julie. Along with her, he also has to deal with potty training and parental wrangling.
This follow-up to the 1989 hit "Look Who's Talking" finds Mikey, the talking baby now a toddler just embarking on the adventure of toilet training. Mikey's accountant mom and her cab driver boyfriend are married and squabbling over their respective careers and differing lifestyles. In the midst of it all they accidentally conceive Mikey's baby-sister Julie whose thoughts are expressed in the voice of comedienne Roseanne Barr.