For good reason. The 78-year-old actress made her debut as Rhoda Morgenstern on The Mary Tyler Moore Show in 1971, playing a character that led to Harper getting her own hit sitcom, Rhoda, which made her a 1970s icon.
“She was such a giving person,” Harper—who has been battling incurable brain cancer for past four and a half years—tells PEOPLE in an exclusive interview in this week’s magazine.
“She used to sit there on the set doing needlepoint endlessly while everyone would run their lines.”
Moore, who waged her own battle with diabetes for years, used her needlepointing skills to create gifts for each of her castmates.
“She stitched out everyone’s initials with her hat, the one she throws up in the air at the beginning of her show, hanging off the letters,” says four-time Emmy winner who recently taped episodes of The Simpsons and American Dad, and plays a woman with Alzheimer’s in the Oscar-qualified short film My Mom and the Girl.
“It was incredibly sweet of her and I can’t even begin to imagine how long it must have taken.”
For more of Harper’s story, pick up the latest issue of PEOPLE, on newsstands now.
Several years before her death at 80 in January 2017, Moore gave Harper a massive framed vintage French advertising poster that bore the same name of a movie the two had worked on.
“We still have it around here somewhere,” Harper says, glancing around the Santa Monica condo she shares with her husband, Tony Cacciotti, who has become her tireless caregiver, constantly monitoring her health, checking in with oncologists and making sure eats healthy and exercises on a daily basis.
But there was one gift that Moore gave Harper that she’s never discussed.
“She taught me to divorce,” Harper says with a mischievous smile, recalling the day Moore pulled her aside during a rehearsal of Rhoda and whispered that she was separating from her second husband.
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“I was very shocked because she hadn’t told anyone yet.”
The revelation, Harper says, “ignited” her to make up her mind to finally end her own deteriorating first marriage, paving the way to her eventual union with Cacciotti in 1987.
For Harper, that was perhaps the greatest gift her longtime friend could have ever given her.
“He’s the reason I’m still here,” she says.