Other stars, like Keeping Up With the Kardashian's Kris Jenner, took to social media to pay tribute.
"I'm so sad to hear about the passing of Jackie Collins..my love and prayers go out to her family and friends and to her sister Joan," she wrote. "What an amazing woman.... It was a joy and honor to have known her."
Jackie was diagnosed with stage 4 breast cancer over six years ago, but she chose to keep her illness as private as possible.
Collins was a true legendary author. She wrote a total of 32 books, all which landed on The New York Times bestsellers list. In addition to Joan, Collins is survived by her three daughters, Tracy, Tiffany, and Rory, and her younger brother, Bill.
"It is with tremendous sadness that we announce the death of our beautiful, dynamic and one of a kind mother, Jackie Collins, who died of breast cancer today," the Collins family confirmed to ET Saturday in a statement. "She lived a wonderfully full life and was adored by her family, friends and the millions of readers who she has been entertaining for over 4 decades."
Private services will be held for her family in both the United States and the United Kingdom. They ask that in lieu of flowers, donations be sent to the Susan G. Komen Breast Cancer Organization and Penny Brohn Cancer Care, respectively.
Watch more about Collins' life and prolific career in the video below: