Whitney Houston was sexually abused as a child by her cousin, her family have claimed in a new documentary.

The film – called Whitney – examines the life of the singer, who was found dead in a bathtub in 2012 aged 48.

Mary Jones, Whitney's aunt who found her body, claims Whitney had told her she had been sexually abused by Dee Dee Warwick – sister of singer Dionne – between the ages of seven and nine.

She recalls Whitney saying: ‘Mary, I was [abused] too. It was a woman.’

Whitney Houston's family claim she was abused as a child by a female relative named Dee Dee Warwick. The singer is seen performing on stage during the 2004

Mary Jones (left), Whitney's aunt who found her body, claims Whitney had told her she had been sexually abused by Dee Dee Warwick (right)

(L-R) Producer Vanessa Tovell, Lara Chinn, producer Simon Chinn, producer Pat Houston, Rayah Houston, Ulysses Carter, director Kevin Macdonald, producer Lisa Erspamer and producer Jonathan Chinn attend the screening of 'Whitney' during the 71st annual Cannes Film Festival

Asked who it was, she said Miss Houston replied: ‘It was Dee Dee Warwick.’

Her brother Gary Garland also speaks about their childhood in the documentary and discloses his greatest trauma was being abused ‘by a female relative’.

But Whitney never told her mother Cissy Houston about the alleged abuse because she ‘was ashamed’, according to her aunt. And a relative said Cissy would have attacked Dee Dee.

Mary claimed the abuse made Whitney ‘question her sexual preference’ – prompting her to demonstrate that she was heterosexual by marrying Bobby Brown.

Whitney was abused as a child, her family has claimed. The singer could not admit the abuse to her mother, it is claimed

Their marriage, between 1992 and 2007, was peppered with violence and drugs. Their daughter Bobbi Kristina Brown died in 2015 at 22.

Brown said Whitney was bisexual and once dated her best friend and assistant Robyn Crawford.

Dee Dee Warwick – 18 years older than Whitney – became addicted to drugs and died aged 63 in 2008.

One source close to the Warwick family said: ‘Dee Dee was openly lesbian in the music industry. Not necessarily in public, but I don’t think that was a secret within the music industry.

Singer Whitney Houston accepts the Winner of International - Favorite Artist Award onstage at the 2009

Celebrities have flocked to Cannes for the film festival where they will watch the new film Whitney

American singer and actress Whitney Houston (1963 - 2012) looks over the picket fence of her mother's home in West Orange, New Jersey in 1985

‘Whitney felt closer to Dee Dee by virtue of them sharing a similar orientation. It is interesting that there is that connection.’

'Whitney' director Kevin Macdonald spoke about the claim during the premiere screening of the film at the Cannes Film Festival on Wednesday.

Macdonald told Deadline he interviewed her aunt Pat and brother Gary.

'He told me that he was abused by a woman in the family, and Pat Houston told me that, yes, Whitney had said to her, "This is what happened,"' the director said in a statement to Deadline.

'So at that stage, I’d had the confirmation that something had happened, but I didn’t know who it was.

'And then, on the next interview, Gary did tell me who it was. This was at the very end of filming, two weeks before we locked the cut.'

Macdonald then spoke with Mary.

The film – called Whitney – examines the life of the singer, who was found dead in a bathtub in 2012 aged 48

'She told me Whitney’s point of view on this, and what Whitney had told her in detail, and how important she felt it was for understanding Whitney, but how scared everyone was to talk about it.

'So, yeah, the film changed radically in the last weeks of editing it, which I guess, as a detective, is the result you want.'

Macdonald added that he questioned whether it would be appropriate to release the claims.

'Obviously it’s such a disturbing allegation, and we did have a lot of debate about it,' he said.

'How do you present material like this, and how do you do it in a way that’s going to be fair to the family and to somebody who’s accused who is also deceased?

'But once we got there, I felt like we had an obligation to use this.'

Both Dionne, 77, and Dee Dee Warwick sang with Whitney’s mother in the New Hope Baptist church choir in Newark, New Jersey.