Patty Duke, who won a supporting actress Oscar playing Helen Keller in “The Miracle Worker,” starred in 1960s sitcom “The Patty Duke Show” and served as president of SAG, died Tuesday. She was 69.

Her manager, Mitchell Stubbs, confirmed that she died early Tuesday of sepsis from a ruptured intestine. “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.

Her life took dramatic turns: As a child actress, she was exploited by her managers and became a young Oscar winner and then a wholesome TV star, followed by struggles with drug addiction and mental illness and eventual stability as head of SAG and a mental health advocate. She served as president of the Screen Actors Guild from 1985 to 1988, succeeding her “Patty Duke Show” co-star William Schallert.

The actress was a popular teen star with her own TV series, “The Patty Duke Show,” which ran from 1963 to 1967 and garnered her an Emmy nomination. In the show she portrayed two cousins with distinctly different personalities (it was not known at the time that she suffered from bipolar disorder).

After “The Patty Duke Show” ended, she surprised fans of her wholesome sitcom by taking a memorably campy role as an alcoholic, drug addict singer in 1967’s “Valley of the Dolls.”

She won an Emmy for 1970 TV movie “My Sweet Charlie” and appeared in several TV shows during the 1970s and ’80s, winning another Emmy for miniseries “Captains and Kings” and a third for a “Miracle Worker” revival.

Born Anna Duke, she was groomed to be a child actress at an early age when her unstable mother turned over her care to exploitative talent managers John and Ethel Ross. After starring on Broadway as the blind advocacy pioneer Helen Keller in “The Miracle Worker” opposite Anne Bancroft, she reprised the role on the big screen. At 16, she was the youngest-ever Oscar winner at the time.

In her memoir, “Call Me Anna,” she wrote that despite being a top TV star, her teenage years were miserable and the Rosses encouraged her to take alcohol and prescription drugs starting when she was 13.

She was married four times — to director Harry Falk, Michael Tell (their brief marriage was annulled), actor John Astin and Michael Pearce — and had relationships with men including Desi Arnaz Jr. Tell was the biological father of her son, Sean Astin, who has appeared in films including “Goonies” and the “Lord of the Rings” movies.

Duke remained active in TV throughout the 1990s and 2000s. She appeared in a slew of TV movies and toplined several short-lived series including ABC’s 1985 effort “Hail to the Chief,” in which she played the first female president; “Karen’s Song,” an early Fox network series in 1987; and NBC’s “Amazing Grace,” which aired in 1995. Her recent TV appearances included guest shots on “Glee,” “Drop Dead Diva,” “Hawaii 5-0” and “Liv and Maddie.”

Astin tweeted a tribute to his mother later on Tuesday.