Ernie writes a play and volunteers Steve's services for his father-and-son night, so he dons a heavy robot costume. The family leaves early, and Steve finds himself alone on the street, helpless in his non-removable suit.

Ernie packs a suitcase, ready to leave home, after he fails to win a cup for the family trophy shelf. He eagerly goes into training, planning to win a school track award, convinced that he won't really be a member of the family until he too can provide a trophy.

Other fathers help their sons in a school science fair, but Steve tells Ernie he's on his own. Soon his project turns to disaster when his very crudely built electric clock absolutely refuses to run. After vainly pleading that most of his classmates are getting parental help, on the day of the fair, Ernie must be forced to go to school.

Bored because he has been left at home alone on a day off from school, Ernie goes on a search for movie stars. The boy loses his footing on a steep path and falls into Zsa Zsa Gabor's swimming pool in Beverly Hills. The glamorous lady invites him in until his clothes dry and later takes him to a real movie studio. Now the whole family as well as the police are searching for Ernie.

With three babies to look after, Dr. Osborne says Katie is completely exhausted and he prescribes a couple of days bed rest. She flies to Santa Barbara to be with her mother. While she is away the family must hire three cleaning ladies to restore the house back to normal.