NPR's guide to the running gags from the show.
Buster is unable to handle the stress of everyday life.
9 episodes feature this joke:
Buster panics when Lucille and George Sr. tell Michael of their upcoming divorce.
Buster is scared of the Queen Mary in a flashback.
Lucille: "No one will be there to hear your screams." Buster: "Aaaaaaaaah!"
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Sources: Joke data compiled by Adam Cole / NPR. Episode metadata from The TVDB via a Creative Commons Attribution 3.0 United States (CC BY 3.0 US) license.