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. (November 2016)
Flanagan was born in New York City on December 26, 1952 and grew up in Costa Mesa, California, with his mother, Kathy; father, Robert; brothers John and Tim; and sister, Patricia. In childhood, Flanagan was diagnosed with cystic fibrosis, from which his sister, Patricia, who died at age 21, and a second sister, who died soon after birth, also suffered. At age 14, in 1967, Flanagan was named the first poster child for the North Orange County chapter of the National Cystic Fibrosis Research Foundation.
Flanagan graduated from Costa Mesa High School, and studied literature at California State University, Long Beach and the University of California, Irvine. He moved to Los Angeles in 1976.
On January 4, 1996, Flanagan died from complications of cystic fibrosis at 43. He was survived by his wife and close artistic collaborator Sheree Rose.
The final years of Flanagan's life, including his death, are the subject of the Kirby Dick documentary SICK: The Life & Death of Bob Flanagan, Supermasochist. Flanagan's participation in the film was contingent upon his death being part of the completed project.