Roadside Attractions(NEW YORK) — Whitney Houston’s sister-in-law, Pat Houston, says the new Whitney documentary, which opens in theaters Friday, is special because it’s endorsed by her family — the only ones, says Houston, who “know the story.”

“This documentary comes from her family, and in order to tell the story, you have to know the story,” Houston tells ABC Radio. “You’re witnessing people that have dealt with her, with her emotions, from the day she was born, until the day she passed, so that’s the difference.” 

Pat Houston serves as one of the executive producers of the documentary, which was directed by Kevin Macdonald.  It features archival footage of Whitney from her younger years to the height of her fame, including her contentious relationship with ex-husband Bobby Brown. We also hear from Whitney herself, as well as fans and family members, who discuss the late singer’s immense talent.

In addition, the film makes the shocking allegation that the late superstar, as well as her half-brother Gary, were abused by their cousin Dee Dee Warwick when they were kids. 

Pat Houston says the film is not sugar-coated and reveals Whitney’s trials, and well as her triumphs.

“It’s a cautionary tale for anyone,” she says. “She was human, and like I said in many interviews, no one is exempt from harsh realities, not even her.” 

Among those interviewed for the documentary: Whitney’s mother, Cissy Houston, music executives Clive Davis and L.A. Reid, and one of Whitney’s producers, Babyface.

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