Whitney filmmaker Kevin MacDonald unintentionally exposed a family secret Whitney Houston took to her grave.

The documentary premiered at the Cannes Film Festival on Thursday, May 17, and it revealed Houston was sexually abused by Dee Dee Warwick, her cousin and sister of Dionne Warwick. She was a Grammy-nominated singer who sang backup for high-profile acts including Aretha Franklin, Wilson Pickett and Cissy Houston, Whitney’s mother and Dee Dee's aunt.

Houston’s former assistant Mary Jones said the singer told her about the abuse after Jones spoke about a family member’s experience.

“[Houston] looked at me and said, ‘Mary, I was molested at a young age, too. But it wasn’t by a man—it was a woman,’” Jones said in the film.

“She had tears in her eyes. She says, ‘Mommy don’t know the things we went through.’ I said, ‘Have you ever told your mother?’ She says, ‘No.’ I said, ‘Well, maybe you need to tell her.’ She said, ‘No, my mother would hurt somebody if I told her who it was.’ She just had tears rolling down her face, and I just hugged her. I said, ‘One day when you get the nerve, you need to tell your mother. It will lift the burden off you.’”

Houston’s brother, Gary, also addressed the abuse during the film.

“Being a child—being seven, eight, nine years old—and being molested by a female family member of mine,” he said. “My mother and father were gone a lot, so we stayed with a lot of different people . . . four, five different families who took care of us.”

According to Vanity Fair, MacDonald became suspicious while he was combing through materials and footage for the documentary. He says the way Houston carried herself tipped him off.

“There was something very disturbed about her, because she was never comfortable in her own skin,” MacDonald said. “She seemed kind of asexual in a strange way. She was a beautiful woman, but she was never particularly sexy. I’ve seen and done some filming with people who have suffered childhood sexual abuse, and there was just something about her manner that was reminiscent to me of that sort of shrinking—a lack of comfort in her own physicality that felt, maybe that is what it was.”

MacDonald said he had a hard time getting information from Houston’s circle because “so many people I spoke to were just untruthful to me, just bullshitting. I never experienced that in any documentary before.”

MacDonald decided to edit the whole film around the revelation. Dee Dee Warwick died in 2008. Houston died in 2012 after she was found unresponsive in a bathtub. The documentary will be released in theaters July 6.

Whitney documentary

Get relevant content delivered to you once a week