Kimberly decides to transfer to Willis' school and gets into a confrontation when she tries to join the all-male swim team. The Drummonds get a new housekeeper named Pearl.

After learning that Joey, a new boy at his school has no friends, Arnold takes it upon himself to befriend him and take him home to meet his family. While there, he convinces Willis to become a "big brother" to Joey. As a result, everyone at the Drummond household take such a shine to Joey, that Arnold becomes jealous and decides to run away.