Caitlyn Jenner’s Biographer Found Dead on Los Angeles Hiking Trail

Caitlyn Jenner’s friend and biographer William Hasley was found dead on a Los Angeles hiking trail on June 6. He was 78.

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Caitlyn Jenner has lost a longtime friend.

William Hasley, who worked as a ghostwriter on the Olympian’s 1996 motivational book Finding the Champion Within, died on June 6, according to the Los Angeles County Medical Examiner records viewed by E! News. He was 78.

Hasley was found in an area near Runyon Canyon, the L.A. Fire Department told the New York Post. Authorities said air rescuers attempted to save him but were unsuccessful.

“LAFD Air Operations lowered rescuers to the patient,” an LAFD spokesperson said in a June 9 statement to the outlet, “and medical treatment was administered.”

Hasley was pronounced dead at the scene. No cause of death has been shared at this time.

In addition to being a prolific author, Hasley was also a screenwriter who worked on cartoons like The Smurfs and Fat Albert and the Cosby Kids. It was his work on Fat Albert that got him involved with the Special Olympics, a role he was particularly excited about as he was a former football player and cross-country athlete at Marshall University, according to the biography on his website.

He also worked on NBC’s Star Salute to the U.S. Olympic Team in 1984, during which time he met Jenner. As Hasley shared in his bio, the two “became fast friends and Jenner commissioned [Hasley] to write a motivational book about his championship philosophy entitled, Finding the Champion Within for Simon & Schuster.”

The book was published in 1996 and offered readers a 10-step program to reboot their lives.

Ron Galella, Ltd./Ron Galella Collection via Getty Images; Steve Granitz/FilmMagic

Hasley then continued his work as ghostwriter with Passion, Profit & Power for Marshall Sylver and The Slight Edge for Jeff Olson.

Besides books, he wrote for ’90s series The Young Riders and Swift Justice. He also developed several pilots, including Borderline Heroes, which was sold to ABC, and the show Brooklyn District for Universal.

While at Universal, Hasley worked as a writer on a film titled Defiance alongside Gerald Green and Oliver Stone, according to his website. He also taught writing at the University of California, Los Angeles.

Hasley was previously married to Bold and the Beautiful actress Robin Riker.

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