While she's made few public appearances since being diagnosed with cancer in 2013, Valerie Harper is returning to the silver screen in a big way.
In My Mom and the Girl, Harper plays Nanny, a former singer now suffering from Alzheimer's. Nanny's illness is turned into a gift when she encounters an unruly girl while roaming the streets of East Los Angeles, and her fearlessness takes them on an enlightening adventure.
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"I liked the way it was written," Harper tells ET. "I don't know a great deal about Alzheimer's -- just what it does."
The part hits close to home for Harper, as she continues to battle her own illness.
"You wake up and go, 'Oh! I'm here, another day to live!'" Harper shares. "I've had a great long [life], and great stuff's happened to me and my darling husband."
Her husband of nearly 30 years, Tony Cacciotti, was with her a year ago when Harper collapsed while doing a summer stock play in Maine. She was airlifted by helicopter to the hospital.
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"My husband was the one who caught it," Harper said at the Glioblastoma Multiforme (GBM) Heroes Awards in San Antonio, Texas, last year. "My husband was the one who got it going. My husband is the one who got me in the hospital. It was incredible."
At the time, the 76-year-old actress explained that a complication with her cancer treatment caused a "blockage" that was preventing her medication from working properly, which is what led to her collapse. By that point, Harper had already long outlasted any medical predictions given after her initial diagnosis.
"I probably had three months because they don't have a cure for the lining," she says. "I don't have brain cancer -- it's in the lining of the brain, another area."
At a special screening of her new film, based on a true story, Harper was supported by fellow TV icon's Dawn Wells (Gilligan's Island) and Donna Mills (Knots Landing).
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"She is a wonderful actress," Wells tells ET. "This film is a labor of love."
"She's such a lovely woman and I'm so happy to see her looking so well," adds Mills.