Caitlyn Jenner is “numb with shock” over the shock death of her longtime friend and manager Sophia Hutchins.

Hutchins had regularly referred to Jenner as a parental figure in interviews.

Hutchins, 29, is believed to have collided with a car while riding an all-terrain vehicle on a road close to Jenner’s property in Malibu, California, last week, before the ATV plummeted into a ravine.

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A source told RadarOnline.com: “Jenner is numb with shock. She is absolutely devastated and can’t believe what’s happened. Hutchins was a big part of her life.”

TMZ previously reported that emergency services were called, but Hutchins was pronounced dead at the scene. No one else is believed to have been injured in the accident.

Caitlyn Jenner is said to be ‘numb' following the death of her manager Sophia Hutchins last week. Credit: AAP

Hutchins took over managing Jenner’s career in 2017 following the reality star’s divorce from Kris Jenner. She appeared in her reality show I Am Cait, and even lived with the star at her Malibu home.

She explained the career move in an interview with the New York Times in 2019, insisting she just wanted to protect her friend at a vulnerable time in her life.

“I saw nobody was managing her, and there were all these people taking massive advantage,” Hutchins told the publication.

“And I was saying: ‘Caitlyn, if I don’t step in here and start managing you, you’re going to go broke’.”

“Caitlyn is a parent to me. I have said that a million times. It is a parental, familial relationship,” she said.

The pair became so close, they were forced to deny speculation they were romantically involved.

Hutchins is believed to have maintained a good relationship with Jenner’s ex-wife Kris and daughters Kendall and Kylie Jenner, while she also appeared in a campaign for SKIMS - the clothing brand run by Jenner’s stepdaughter Kim Kardashian.