Updated 2:56 PM with SAG-AFTRA statement: Patty Duke’s co-stars and colleagues at the Screen Actors Guild (where Duke served as president from 1985-88) responded with sadness at news of the actress’ death today. Duke was the second woman to be nominated to the position of SAG president after Kathleen Nolan.

“It is a difficult time for the union, and Anna’s death is another devastating loss to our union family. She was a committed unionist and a champion for her fellow members,” said SAG-AFTRA Acting President Gabrielle Carteris in a statement. “I had the honor of working with Anna and she had an amazing energy, resolve and positive spirit. She will be sorely missed and our thoughts and prayers go out to her family.”  The SAG-AFTRA statement praises Duke for overseeing the establishment of the SAG Foundation; the relocation of the Guild headquarters; the creation of a low-budget motion picture agreement that offered incentives to productions that hired women, minorities, seniors and disabled performers; and the payment of the one-billionth dollar in residuals to a SAG member. Duke also led a six-week animation strike and a three-week commercials contract strike, and fought the recurring threats of so-called “right-to-work” legislation and runaway production. In 1988, she resigned from the presidency in order to produce the TV movie of Call Me Anna, in which she also starred as herself.

“She was a great star and a great person,” Ed Asner told Deadline. “I will miss her existence here on this earth.” Asner, who preceded Duke as SAG president, said that “those were wild times and she acquitted herself admirably. Unfortunately, things went downhill after that.” In 1986, she led the guild through contentious negotiations for a new film and TV contract. There were threats of a strike — the membership even voted to authorize one — but in the end the talks were settled without a work stoppage.

Melissa Gilbert worked with Duke in the 1979 TV movie version of The Miracle Worker. Duke played Anne Sullivan while Gilbert portrayed Helen Keller, the role that Duke originated on stage and won an Oscar for in the 1962 movie. Like Duke, Gilbert too was a SAG president (serving two terms). The two would work again in the 1994 TV film Cries From the Heart. Gilbert tweeted out three responses, quoting Keller:

Duke’s son is Lord of the Rings actor Sean Astin, who took to Twitter:

Astin’s co-star and friend Elijah Wood added:

Oscar-winner Octavia Spencer, who worked with Duke on the 2002 Hallmark movie Little John had this to say:

Martha Plimpton, who worked with Astin on Goonies, tweeted:

Duke guest-starred as Grandma Janice on Disney Channel’s Liv and Maddie. Actress Jessica Marie Garcia from the show tweeted out this pic:

Liv and Maddie EP John Beck took to Instagram:

Duke also won three Emmys and two Golden Globes. She was diagnosed with bipolar disorder in 1982, and she became a vocal advocate for mental health care, detailing her fight with the disease in her 1992 autobiography Brilliant Madness: Living with Manic Depressive Illness.

Los Angeles Fox 11 Good Day LA host Steve Edwards co-hosted AM Los Angeles in the late 1980s with Duke. Astin called into Edwards’ show and the two remembered Duke. The two speak about her powerful and tragic childhood, how Duke’s turn as Helen Keller inspired her to help others, as well Astin taking over his mother’s advocacy work in educating others about mental illness. Here’s that footage: