Picture: Dionne Warwick at ABC Studios to appear on ABC's 'Good Morning America' New York City, USA - 08.03.12
Soul icon Dionne Warwick is convinced her cousin Whitney Houston died from a heart attack.
The I Will Always Love You singer was found dead in the bathtub of her Los Angeles hotel suite on 11 February (12), hours before she was scheduled to attend mentor and friend Clive Davis' annual pre-Grammys party.
An autopsy proved inconclusive and the cause of death has been deferred pending toxicology reports, but Warwick believes she already knows how the superstar died.
She tells U.S. news show Entertainment Tonight, "You know, in all honesty, I think she had a heart attack; that's what I think happened to her."
But the Walk On By singer is hesitant to speculate whether reports suggesting alcohol and prescription pills played a part in Houston's death are true, adding, "I don't know if it's that (drugs) or not. I think her heart just gave out."
The Los Angeles County Coroner previously requested all medical records from Houston's doctors to determine what drugs she was taking at the time of her passing.
The singer had a history of drug addiction and twice checked into rehab to control her substance abuse.