Amanda Peterson's mom reveals dark secret from her childhood (VIDEO)

Sep 15, 2015 at 9:46 a.m. ET

Amanda Peterson's death in July of this year shocked fans, but now the late actress' mom, Sylvia, has revealed something about her dark childhood that "affected her forever."

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The Can't Buy Me Love actress died of an accidental morphine overdose, and on Monday, her mother revealed during an interview with The Doctors that she had been raped when she was just 15 years old.

"At the height of Mandy's career, she suffered a very serious trauma. She had been raped," Sylvia, told the program. "She just felt so ashamed. She didn't want people to know."

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Peterson's sister, Anne-Marie also spoke to the program, revealing that her sister did not tell her about the sexual assault.

"I think for her to carry the secret, this burden of the assault, must have just been overwhelming," Anne-Marie said.

The Listen to Me star's father, James, also weighed in on his daughter's past, saying that she changed significantly after the rape and became "more defensive, less trusting, some of the sparkle was gone." She also began suffering from "bipolar problems."

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Peterson started using drugs as a young woman, something that her parents detailed during the interview. They also went on to speak about the moment they first heard the news that their daughter was dead.

"My heart is wrecked," Sylvia confessed.

For more, watch the video below.