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

Sir, I got carsick in your office.

Ralph

Mr. Burns: (reading Homer's letter) "Dear Mr. Burns. I'm so glad you enjoyed my son's blood, and your card was just great." Why Simpson, you've made my day, you're a true gentlemen.
Homer: Well I-
Mr. Burns: Hello, there's more. (continues reading) "In case you can't tell, I'm being sarcastic. You stink! You are a senile bucktoothed old mummy with bony girl arms and you smell like an elephant's butt!"