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The Bun-Bun Brothers are a group of rabbits who sang "Zip-a-Dee-Doo-Dah" on episode 420 of The Muppet Show. Kermit originally turned them away due to show business politics: if he had singing rabbits on, he'd have to cancel the dancing carrots. However, when Alan Arkin was incapacitated by Dr. Bunsen Honeydew's Ultra-Powerful Jekyll-Hyde Potion, Kermit sent them onstage.
Their fifteen minutes of fame were cut short when Arkin appeared on stage to mercilessly ravage the fluffy bunnies. One of them asked Statler and Waldorf if he could hide in their box, but Statler called out to Alan that he missed a victim as Waldorf threw the bunny down to the potion-possessed guest star.
The Bun-Bun Brothers exacted revenge by the show's closing when they get a dose of the potion themselves.