Told to babysit Maggie by Mom, Bart and Lisa do a crummy job of babysitting their younger sister. Maggie accidentally electrocutes herself by shoving a fork into an electrical socket, falls down the stairs, climbs onto the roof to catch a butterfly and falls. Lisa, concerned she heard a noise, is threatened by Bart. Maggie comes out from a bush with a butterfly in her hand. Mom arrives home, unnoticed. Then a butterfly flutters away from Maggie's hand. As Maggie wails, Bart says that Maggie's such a baby.