Alison arngrim abused by brother

Alison Arngrim, the actor who played the angry, conniving brat Nellie Oleson on the popular 1970s TV series "Little House on the Prairie," says there's a reason she was so convincing in the role: She was a victim of childhood sex abuse.

Arngrim was 11 when she took the role of the little girl America loved to hate, and she says being able to vent her rage may have saved her sanity.

"When you live with abuse, you have a lot of rage and anger, and I had a place to actually take it and vent it as Nellie," Arngrim told The Today Show Wednesday.

"It's done me so much good, I can't even describe it."

Arngrim, 48, first revealed that she was sexually abused by a family member starting at the age of 6 on Larry King in 2004. But now she says she's telling her story in all its complexity through a new book, "Confessions of a Prairie Bitch: How I Survived Nellie Oleson and Learned to Love Being Hated."

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