The third book in a middle-grade spin-off series of Mrs. Piggle Wiggle, from New York Times–bestselling author Ann M. Martin, about a young nanny who fixes problems with wisdom and a little magic. Once in a generation, the Effluvia strikes and it affects everyone differently. Missy wakes one morning to find the upside-down house is . . . right-side up? It's not long before Missy has to quarantine the house. Meanwhile she's still fielding calls from worried parents, and Louie can't keep his sticky fingers from taking other people's things! But Missy's magic cure might just do the trick, and even teach some valuable lessons along the way. This delightful middle-grade series will be sure to draw in readers both new and old to this revitalization of a classic series.