Author: Rachel Vail
Illustrator: Yumi Heo
Published: Scholastic, 2002

Katie is usually happy. She smiles a lot, puts away her toys, remembers to say please, and is patient with her baby brother (even when he knocks over her beautiful block castle). But sometimes she's Bombaloo. Then, Katie says, "I use my feet and my fists instead of my words. My toys end up all over the floor - and so does my brother." When Katie is Bombaloo, she is sent to calm herself down. But when she is Bombaloo, she is angry and hates everyone. Soon, though, she does feel sorry (and a little frightened). Her mom is ready to hug her and help her clean up the mess, and she and little brother build a new castle together. Mom Rachel Vail adeptly captures the child's emotions while Yumi Heo's unique illustrations depict her changing moods.