PRESS UPDATE : PEOPLE MAGAZINE .. SEPTEMBER 25TH 2015 .

Jackie and Tiffany

For all the glamour and Hollywood charm that helped turn Jackie Collins into a star, there was quite a different side to the beloved novelist: that of a down-to-earth mum to her three daughters and devoted grandmother to six kids who called her "Jac Jac". 

"She was always there for us," says Tiffany Lerman, 48, middle daughter of Collins, who died on Sept. 19 after a 6-year battle with breast cancer, at 77. 

"Growing up, she would wake up with us every day, make us breakfast, take us to school, come back and write the entire day, pick us up from school, bring us home and make us dinner ... She was a bit of a superwoman."

Jackie with newborn Rory and Tiffany in 1969

While she was a prolific writer who relished her work, family came first. "She kept her priorities straight," says the author's youngest daughter, Rory Lerman Green, 46, who moved her family from London to L.A. after Collins' 2009 diagnosis to be close. 

"They led a glamorous life," says Rory of Collins and her husband Oscar, married for 26 years until he died of prostate cancer in 1992. "But at home she was normal." 

Indeed, Collins told PEOPLE on Sept. 14 in her final interview, "Everybody thinks I'm glamorous, which I'm not. My sister (actress Joan Collins) is glamorous." 

At home, she said, "I'll be in the kitchen cooking roast chicken and roast potatoes and just sitting around with my kids." 

"Family has always been really important to her," says Rory, "and she's always been loving." 

And well-loved – in life and in memory. 

"We are utterly heartbroken," Collins' daughters told PEOPLE exclusively two days after her death. "She has left us with an extraordinary legacy of love and creativity." 

Overwhelmed by the outpouring of well-wishes from family, friends and fans, Collins' daughters are comforted by their mother's enduring legacy. 

"She has left old and new fans alike with endless hours of fun and entertainment," they tell PEOPLE. "She followed her passions and she lived to tell stories and writing brought her so much joy. We know her vibrant and indomitable spirit will stay alive through her work for many years to come. It's hard to imagine life without her, but we all feel she is with us in so many ways." 

For more on Jackie Collins, pick up the new issue of PEOPLE, on newsstands Friday.