Image copyright Getty Images Image caption Houston died at the age of 48 in 2012

A new documentary about late singer Whitney Houston alleges that her cousin, Dee Dee Warwick, sexually abused her.

Houston's half-brother Gary Garland-Houston and her assistant, Mary Jones, both made the claims against Dee Dee, who died in 2008.

The film, Whitney, is directed by Scottish filmmaker Kevin Macdonald.

Dee Dee Warwick is the younger sister of soul singer Dionne Warwick and was the niece of Houston's mother.

Whitney debuted in Cannes on Wednesday night.

The Warwick family has been contacted for comment by the BBC.

Image copyright Getty Images Image caption Kevin Macdonald with Whitney's niece Rayah Houston and the film's producer, Whitney's sister in-law Pat Houston

Houston, who sold millions of records and had hits with songs like I Will Always Love You and I Wanna Dance With Somebody, died in 2012 at the age of 48.

She drowned in a bath in a hotel and the coroner ruled that cocaine use and heart disease were factors in her death.

Houston ended her volatile 15-year marriage to singer Bobby Brown in 2007.

Their daughter, Bobbi Kristina Brown, died at a hospice in 2015 at the age of 22, six months after she was found unresponsive in a bath.

Film writer and producer Kaleem Aftab was among those to praise the film.

Skip Twitter post by @aftabamon So Whitney by Kevin Macdonald is way better than the Nick Brookfield doc with some great anecdotes and a story of abuse that scarred her life but structured in familiar documentary style with talking heads et al — Kaleem Aftab (@aftabamon) May 17, 2018 Report

But he added a note of caution.

Skip Twitter post 2 by @aftabamon Never sure what to think when accusations are made about people who have no chance to defend themselves. Not that I doubt the substance of the accusations in #Whitney but film hangs on this story of abuse! #whitneyhouston — Kaleem Aftab (@aftabamon) May 17, 2018 Report

Fellow writer Ali Benz was also a fan.

Owen Gleiberman, film critic at Variety, wrote: "We don't necessarily need another documentary to remind us of what a powerful and transformative singer Whitney Houston was. Whitney does something more essential: It plunges into the 'Why?' and comes up with a shatteringly convincing answer."

Tom Grierson, writing in Screen Daily, wrote: "Whitney is strongest when it connects Houston to the larger history of Black America, illustrating how this glamorous performer grew up in poverty and never entirely escaped the obligation of helping to pull up her underprivileged family members."

The Times's Ed Potton gave it a four-star review while The Telegraph's Tim Robey was more lukewarm, giving it three stars and writing: "The film is oddly unmoving as a memorial, but as with Amy Winehouse, it inspires a collective mea culpa for the feeding frenzy of public judgement that only turned to sympathy when it was far too late."

David Rooney, a critic for The Hollywood Reporter, wrote: "It's a riveting narrative, and even those not among Houston's more passionate fan base will find it an emotionally wrenching experience."

Whitney will be released in UK and US cinemas on 6 July.

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