Grampa relieves his Air Force days on The Simpsons. "Let's Go Fly a Coot" is the 20th episode of the shows 26th season.
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Homer finds out that Grampa was once a famous wrestler on The Simpsons. "Gorgeous Grampa" is the 14th episode of the show's 24th season.
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It's that special time of the year on The Simpsons. Look for the family to see its future on the episode "Holidays of Future Passed."
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A picture of Abe Simpson, aka Grandpa Simpson, Homer's rambling, senile father on The Simpsons.
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The Simpsons Quotes

(Picking out a Tuxedo for Bart. He doesn't look pleased with his puffy shirt tuxedo.)
Bart: (frowning) Isn't this shirt kinda gay?
Clerk: Last time I checked, pirates weren't gay.
Homer: Eww, how'd you check?

Wow, now I see why they call you Miss Hoover. You must have been vacuuming for an hour.

Bart