Claudia"s not worried when she hears her newest baby-sitting charge, Betsy Sobak, is a great practical joker. After all, how much harm can one little girl do?Plenty. Claudia breaks her leg as a result of one of Betsy"s mean jokes... and now she"s talking about quitting the club. "Baby-sitting," she says, "is just too dangerous." Kristy thinks Betsy needs to be taught a lesson. She also thinks the Baby-sitters are just the ones to do it.Watch out, Betsy Sobak! The joke war is on!