Jack Burns, a comedian, writer and actor known for writing on “The Muppet Show” and “Hee Haw,” acting on “The Andy Griffith Show,” and his comedy partnership with George Carlin, has died at the age of 86, his manager Peter Santana confirmed to TheWrap Tuesday.

“He has been in senior care for the last two years in good spirits and surrounded by friends and cases of Diet Coke,” Santana said. “He was as sharp as a tack mentally but had not walked for two years. He achieved many great achievements but his most recent was hitting the 31 year sober mark in December. Truly a sweet and talented man.”

Burns began his career in show business in the 1960s by way of his duo with Carlin. The two made a comedy album together in 1963 called “Burns and Carlin at the Playboy Club,” and also had a radio show together at KXOL in Fort Worth, Texas. Burns later partnered with Avery Schreiber, a fellow member of Chicago comedy troupe The Second City, before transitioning to writing and producing for television and films in the 1970s.

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Carlin’s daughter Kelly Carlin shared her condolences on Twitter Tuesday.

“A foundational piece of the Carlin legacy has gone to the big comedy club in the sky. Jack was one of the sharpest motherf—–s I knew,” she wrote. “He shaped my father’s mind in unique ways. RIP Jack Burns.”

Burns’ other acting credits include “Happy Days,” “The Partridge Family,” “Fridays” and “Sour Grapes.” He also wrote on the 1979 “Muppet Movie.”

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He was also an accomplished voice actor, having voiced characters on “The Simpsons,” “Animaniacs,” “Mother Goose and Grimm,” and “Darkwing Duck.”

A foundational piece of the Carlin legacy has gone to the big comedy club in the sky. Jack was one of the sharpest motherfuckers I knew. He shaped my father’s mind in unique ways. RIP Jack Burns. https://t.co/aOPpeysM5I — Kelly Carlin (@kelly_carlin) January 28, 2020