So tragic. Can't Buy Me Love star Amanda Peterson, who died of an accidental morphine overdose back in July, was harboring a horrific secret, the late actress' family revealed on Monday, Sept. 14.

During an interview with The Doctors, Peterson's mom, Sylvia, revealed that her daughter was raped when she was just 15 years old, something she never felt able to talk about, and which "affected her forever."

Peterson, who was 43 when she passed away, shot to fame as high school student Cindy Mancini in the 1987 classic film. But as Us Weekly revealed previously, her life following her stint as a Hollywood celebrity was peppered with arrests, some of which related to DUIs and narcotics.

"At the height of Mandy's career, she suffered a very serious trauma. She had been raped," Peterson's mom, Sylvia, told the program, 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," her mom added. "I think it affected her forever."

Even Peterson's sister, Anne-Marie, did not know about what her sister had endured. "I think for her to carry the secret, this burden of the assault, must have just been overwhelming," Anne-Marie told the program.

"After [the rape], she became more defensive, less trusting, some of the sparkle was gone," Peterson's dad, James, said, adding that she went on to suffer "significant bipolar problems" and dark days, during which she turned to drugs.

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," Amanda's dad, James, explained during the program. "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," he said. "We all have to be more aware, and that doesn't diminish your love."

Watch the heartbreaking interviews in the clip above.

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