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Jeff Conaway - Kenickie
Conaway played Kenickie, a member of the T-Birds clique and friend to John Travolta's Danny in the 1978. He also portrayed Bobby Wheeler on the television show 'Taxi,' which also starred late comedian Andy Kaufman and ran between 1978 and 1983.
Conaway appeared on the sci-fi series 'Babylon 5' in the 1990s as Zack Allan. In recent years, he appeared in small film projects. In 2011, he was working on a thriller called 'Human Factor,' which features 'Buffy The Vampire Slayer' actress Charisma Carpenter, Eric Roberts and Sean Patrick Flanery.
He was married twice - first to Rona Newton-John, sister of the actor's 'Grease' co-star Olivia Newton-John, between 1980 and 1985. He married his second wife, Kerri Young, in 1990. The two later separated. The actor has no children of his own.
Conaway died on May 27, 2011 at the age of 60 after he was taken off life support following a battle with pneumonia and sepsis in a hospital. The actor had battled addictions to cocaine, alcohol and prescription painkillers since he was a teenager and talked about his struggles on the reality series 'Celebrity Rehab with Doctor Drew' in 2008.
(Pictured: Conaway in 'Grease' and his appearance on 'Celebrity Rehab with Dr. Drew' in 2008.)
( Photo / Paramount / VH1)