(CNN) -- Actress Bonnie Franklin, a Tony Award nominee who played a single mom at the center of the hit TV sitcom "One Day at a Time," died Friday of complications from pancreatic cancer.
Franklin was 69.
The woman who played the youngest daughter of Franklin's character on the CBS show, Valerie Bertinelli, said her "heart is breaking" after hearing the news.
"Bonnie has always been one of the most important women in my life and was a second mother to me," Bertinelli said. "She taught me how to navigate this business and life itself with grace and humor, and to always be true to yourself.
"I will miss her terribly."
Actress Mackenzie Phillips later tweeted a picture of her and Franklin, who played her mom on the same program.
"Remembering my friend," Phillips wrote. "Rest in peace."
The Southern California-born Franklin broke into show business 60 years ago, appearing on the "Colgate Comedy Hour" TV show. She racked up roles on programs such as "Gidget," "The Man from U.N.C.L.E." and "The Munsters" before heading out to Broadway after her graduation from UCLA.
Her debut in "Applause" on stage earned her accolades and a Tony nomination in 1970 in the category of featured actress in a musical.
Eventually, she returned to television, including in 1975 landing the breakthrough role of Ann Romano in "One Day at a Time." She played a recently divorced mother of two teenage girls who, together, move to Indianapolis to begin a new life.
"Ms. Franklin helped define and illuminate the role of single-working mothers within the cultural landscape," CBS said in a written statement.
The show, produced by Norman Lear, ran for nine seasons.
After it ended, she scored some jobs directing and acting, most recently in guest spots on the TV Land sitcom "Hot in Cleveland" and the soap opera "The Young and the Restless."
She was the spouse for 29 years of producer Marvin Minoff, who died in 2009, as well as a mother and grandmother.
Franklin died Friday in her home surrounded by family and friends, according to CBS.
"She was a GREAT and comforting role model for single mothers, as I was one of them at that same time," wrote a CNN.com commenter with the handle Gera Merix.
"Bye Bonnie ... Have a good trip to heaven."