Bart's big brother, Tom (Phil Hartman) ends up fighting and injuring Homer at the aquarium.
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The Simpsons Season 4 Episode 14 Quotes

Homer: Remember when I used to push you on the swing?
Bart: I was faking it.
Homer: Liar!
Bart: Oh yeah? Remember this? "Higher, Dad! Higher! Whee! Whee! Push harder dad!"

You're not the only one who can abuse a non-profit organization!

Homer