Sybil loves to play. She enjoys making people laugh, especially at school. Her brother Willie loves being responsible. It's all good until one day Sybil's harmless prank on the school bus gets her into major trouble. She plots revenge on Willie for turning her in to the principal. Sybil's plan involves spray can cheese, basketball shoes, and Sybil's adorable dog, Rex. When the unthinkable happens and Rex is put in jeopardy, Sybil has to rethink every...