The Lost Weekend - S2.E24

Abby convinces Tom to spend the weekend with her parents in Pasadena, leaving the kids alone for the weekend. While they are away, despite a rule against having any non-Bradfords in the house, the kids throw a party, but then the house is overrun with chaos and the kids barely manage to get things back in order before Tom and Abby return. A distant cousins shows up on the Bradford doorstep for the flower children.