Sadie and Ratz by Sonya Hartnett; illus. by Ann James Primary Candlewick 60 pp. 3/12 978-0-7636-5315-6 $14.99 g e-book ed. 978-0-7636-5990-5 $14.99

In Hartnett's first venture into younger reader territory, Sadie and Ratz are the pair of hands that belong to Hannah and get her into trouble. Sadie and Ratz like to "crush things up, twist and scrunch," and most especially they like to jump onto the head of Hannah's little brother, Baby Boy, and try to rub his ears off. In this original take on sibling rivalry, Sadie and Ratz resist, thank goodness, parental advice involving calming yoga positions such as "snowflakes in winter." Only when Baby Boy turns out to be a sneak, lying about domestic graffiti, spilled milk, and a broken clock, does Hannah, pushed to the wall, find the motivation to achieve mastery over her noncompliant appendages. This tale of temper and self-control, told in the first person, is more psychologically sophisticated than is usually found in an early chapter book, but the sensitive drawings and clever book design add significantly to the emotional clarity of Hannah's journey. SARAH ELLIS