Two mischievous pigs, a timid baby-sitter, and an iguana on the loose make for merry mayhem in this lively tale. Geraldine conspires with her younger sibling Willy to oust their new baby-sitter, the bespectacled Mrs. Duffy. Clad in a suitably mousy-gray sweater, she seems easy pickings to the troublesome duo. Readers will gleefully recognize the subversive tactics employed by the pair: tears, tantrums, hiding in a closet, and a staunch refusal to bathe. However, this classic repertoire of antics leaves their sitter unruffled. Undeterred, Geraldine hatches a plan that involves Jerome, their pet iguana. At first, success seems imminent as Mrs. Duffy (who likes to talk in triplicate) gives a satisfyingly alarmed response (“Oh, dear, dear, dear!”) to the sight of Jerome splashing in the tub along with Geraldine and Willy. Things quickly take a downturn as Jerome makes his escape. Here’s where the indomitable Mrs. Duffy shines: scaling tables to rescue the fugitive lizard from its perch atop the bookcase, earning the respect and admiration of the children (and readers). Keller’s (Jacob’s Tree, 1999, etc.) cheeky, colorful drawings are an impish counterpart to the comical tale. Vibrant watercolors depicting the dripping-wet siblings rushing after Jerome wearing nothing but their birthday suits are hilarious, as are the many illustrations that slyly incorporate the elusive Jerome into the pictures. This is sure to strike a responsive chord in readers and their weary baby-sitters alike. As Mrs. Duffy would say, “Yes, yes, yes.” (Picture book. 5-8)