The Insider.com

Nick Offerman is one hilarious husband. The Parks and Recreation actor shared on The Late Show With David Letterman on Wednesday a love song he wrote for his wife Megan Mullally on her 50th birthday titled Rainbow song.

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Guitar in hand, he sang, "You put me on trial and read me my rights. ... But orange you glad I didn't say banana when you made me your b**** and I made you my wife."

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The song continues, "Please enjoy this rainbow song and this gift of leprechaun romance."

Mullally, 53, and Offerman, 42, married in 2003, but on screen, the two play ex spouses Ron Swanson and Tammy on Parks and Rec.