Jody Cortes / WENN 1 / 6
Jody Cortes / WENN 1 / 6

Brittany Murphy's mother Sharon and husband Simon Monjack are speaking out about what they believe caused their loved one's death.

Sharon Murphy tells that she and Monjack think the late actress' death stemmed from a congenital heart murmur. They say that Bittany was diagnosed with the condition in her teens and had received sufficient medical care for it since.

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"We had it checked out every which way you could imagine," Monjack says.

Murphy's mother says her daughter's "bubbly" personality might have fueled rumors of drug use, which she calls untrue. "She never even drank. Maybe a glass of champagne at New Years," Sharon tells the site. "But everyone used to say she was wasted, she was this, she was that. It was hard for anyone to imagine that somebody was so high on life."

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Murphy's mother and Monjack also say the late actress didn't suffer from mental illness or battle an eating disorder. "Do you not think anybody would have picked up on this anorexic, mentally deranged person?" Monjack says. "It's ludicrous."

An in-depth interview with Sharon Murphy and Simon Monjack appears in this week's People magazine, on stands Jan. 22.

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