Mrs. Piggle-Wiggle has gone away unexpectedly and left her niece, Missy Piggle-Wiggle, in charge of the Upside-Down House and the beloved animals who live there: Lester the pig, Wag the dog, and Penelope the parrot, among others. Families in town soon realize that like her great-aunt, Missy Piggle-Wiggle has inventive cures for all sorts of childhood (mis)behavior: The Whatever Cure and the Just-a-Minute Cure, for instance. What is a stressed out parent to do? Why, call Missy Piggle-Wiggle, of course!