Viola Davis shares story of assault at Rape Foundation event

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Viola Davis has spoken about seeing the effects of sexual assault first hand.

The Help actress says her sister was sexually assaulted at age eight and is now a heroin addict and prostitute.

Viola also described her mother and herself as survivors of sexual assault on Sunday at a benefit for the Rape Foundation.

Viola Davis
Viola Davis has spoken about her sister at a Rape Foundation event (Jordan Strauss/AP/PA)

It provides free medical treatment, counselling and legal aid to rape victims plus special services for children.

Viola has been an advocate for the organisation since playing its founder in a 2010 film.

The actress was among the guests of honour at the organisation's annual fundraising brunch.

The event was held at billionaire Ron Burkle's Greenacres estate in Beverly Hills, California.