Story highlights He played the innocent Kent Dorfman, nicknamed Flounder

Furst also appeared in "St. Elsewhere" and "Babylon 5"

(CNN) Stephen Furst, the actor who played the hapless, beanie-wearing frat boy Flounder in the 1978 movie "Animal House," has died at age 63, his son, Nathan Furst, told CNN on Saturday.

"It was from complications from diabetes," Nathan Furst said. "Over the last several years it was getting worse a little bit. Sort of the typical things that tend to happen when you have diabetes a long time."

Furst appeared on TV in "St. Elsewhere" and "Babylon 5," but he was best remembered for his role as the innocent freshman Kent Dorfman in "National Lampoon's Animal House," which ushered in a brand of raunchy comedy.

His character was rejected by other fraternities at the fictional Faber College but got into the hard-partying, rule-breaking frat nicknamed Animal House. Bluto -- the house wild man played by John Belushi in his own breakout role -- gave Dorfman the nickname Flounder. A series of mishaps and humiliations followed.

RIP Stephen Furst pic.twitter.com/8Mp4sOs6r4 — Jake Tapper (@jaketapper) June 18, 2017

Flounder accidentally killed a horse -- apparently by inducing fright -- by firing a pistol loaded with blanks into the air during a midnight prank in Dean Vernon Wormer's office.

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