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The late Amanda Peterson carried a secret for most of her life, one that her family is now revealing and one that her mother said "affected her forever:" she was raped at the age of 15.

During an interview with "The Doctors," Sylvia Peterson said her daughter never spoke about the incident.

"At the height of Mandy's career, she suffered a very serious trauma. She had been raped," Sylvia said, explaining that the man who assaulted her was more than twice her age. "She just felt so ashamed. She didn't want people to know."

She added, "I think it affected her forever."

Amanda died in July of a drug overdose. A toxicology report revealed the former actress had multiple prescription drugs in her system, including anti-anxiety mediation, an anti-psychotic medication, pain medication and opiates. She also had marijuana in her system.

Amanda's dad said the rape actually led her to drugs.

"After [the rape], she became more defensive, less trusting, some of the sparkle was gone,", James Peterson said, adding that she went on to suffer "significant bipolar problems."

Amanda rose to fame in 1987 after playing Cindy Mancini in "Can't Buy Me Love." However, despite this career success, she led a troubled life that saw her in and out of jail for drug use.

On the TV show, the Peterson family went on to talk frankly about their discovery that Amanda was using heroin and meth.

"I want to stress why we're here is to warn and counsel people," James said. "We are among perhaps millions who have gone through these problems. You have to be very well attuned to what your children are doing, what they're saying. We all have to be more aware, and that doesn't diminish your love."