When the boys and girls get sick of having to share the bathroom, they split it into two! The girls' side becomes one big party with no rules, but on the boys' side Dog makes many rules! Boy and Mouse hate it, but they don't want to hurt Dog's feelings. Girl tries to lure them over to the girls' side with all the things they love to play with. Eventually Boy and Mouse sneak over to the girls' side to join in the fun - until Dog confronts them.