Revealing mistake: When Betty goes into labour in the night and goes downstairs with her suitcase, she tries opening the front door. You can see it moving with her pulling. And then when Frank goes to climb out of the window to follow the key, he climbs onto the sink, which almost rolls away, which reveals the fakery of the set.
Some Mothers do 'Ave 'Em (1973)
1 revealing mistake in The Baby Arrives
Starring: Michael Crawford, Jane Hylton, Michele Dotrice, Jessica Forte
Genres: Comedy
Revealing mistake: When Frank is the pixie in Santa's grotto, a young boy fires something at Frank from his catapult. Although Frank reacts as being hit, the boy doesn't actually fire anything at all.
Betty: Don't get so depressed Frank, you've only been out of work two days. Mr Rogers hasn't worked for six months.
Frank: Mr Rogers is 86 years old!
Trivia: Michael Crawford performed all of his own stunts in this series.