Oscar-winning American actress Patty Duke, widely known for the 1960s show "The Patty Duke Show," died on Tuesday, her representative told Reuters. She was 69 years old.

Duke died Tuesday morning in Coeur d'Alene, Idaho from sepsis due to a ruptured intestine, her spokesman Mitchell Stubbs said.

"She was a wife, a mother, a grandmother, a friend, a mental health advocate and a cultural icon. She will be greatly missed," Stubbs said.

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The actress began working as a teen and won a best supporting actress Oscar for her role in 1962's "The Miracle Worker" at age 16. She starred in her own sitcom, "The Patty Duke Show" from 1963 to 1966, and had a role in 1967's "Valley of the Dolls."

She later became president of the Screen Actor's Guild in the 1980s, and also became an advocate for mental health issues after being diagnosed with bipolar disorder in 1982.