Viola Davis Viola Davis

Viola Davis shared a heartbreaking story on Tuesday night about the impact sexual assault has had on her personally.

In a speech at the Stuart House, a California nonprofit that works with child sexual assault victims, the How to Get Away with Murder star recounted that her sister was sexually assaulted in a store when she was 8 years old. When Davis' mother confronted the store owners, she said they told her: "Leave that man alone. He does that to all the little girls."

Though the man was taken into police custody, Davis said the assault did long-term damage to her sister, who is now 39. "A precocious, very intelligent, very creative child grew up to be frail, angry, a drug addict by the time she was 20," the Oscar nominee said, her voice cracking. "Six children, all of which have been taken by social services. A prostitute. An IV drug user."

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Davis speculated that her sister's life may have been different if she had an organization like the Stuart House to turn to.

"When I pray for my sister ... you pray that she finds peace and love and happiness, she gets off drugs. ... If I had a fantasy, I would give her permission to speak, and I would want her in an environment where people heard her. And I would want her to be angry," Davis said. "Her whole life could have been different. And now her whole life is what?"

On How to Get Away with Murder, Davis' character Annalise Keating was also sexually assaulted as a child.

"I wish that I could tell my sister that she's not dirty, and that she should not feel any shame of something that she literally was not responsible for," Davis said. "I wish I could save her life."

Watch Davis' speech here.