By Mo Willems, Author & Illustrator. Gerald and Piggie are best friends. Gerald is careful. Piggie is not. Piggie cannot help smiling. Gerald can. Gerald worries so that Piggie does not have to. In I Will Take a Nap! Gerald is tired and cranky. Will Piggie be in his dreams? Or will she keep Gerald from dreaming at all? For ages 3 and up.