NEW YORK – Patty Duke, who as a teen won an Oscar for playing Helen Keller in “The Miracle Worker,” then maintained a long career while battling personal demons, has died at the age of 69.

The actress died early Tuesday morning of sepsis from a ruptured intestine, according to her agent, Mitchell Stubbs. She died in Coeur D’Alene, Idaho, where she had lived for the past quarter-century, according to Teri Weigel, the publicist for her son, actor Sean Astin.

Duke astonished audiences as the young deaf-and-blind Keller first on Broadway, then in the acclaimed 1962 film version, appearing in both alongside Anne Bancroft as Helen’s teacher, Annie Sullivan (who won an Oscar of her own).

Then in 1963, Duke burst on the TV scene starring in her own sitcom, “The Patty Duke Show,” which aired for three seasons. She played dual roles as identical cousins Kathy, “who’s lived most everywhere, from Zanzibar to Barclay Square” while (according to the theme song) “Patty’s only seen the sights a girl can see from Brooklyn Heights. What a crazy pair!”

In 2015, she would play twin roles again: as a pair of grandmas on an episode of “Liv and Maddie,” a series on the Disney Channel.

“We’re so grateful to her for living a life that generates that amount of compassion and feeling in others,” Astin told The Associated Press in reflecting on the outpouring of sentiment from fans at the news of her death.