LOS ANGELES - Jeanne Cooper, 84, the enduring soap-opera star who played grande dame Katherine Chancellor for nearly four decades on

The Young and the Restless

, died Wednesday in her sleep, the actor Corbin Bernsen, her son, wrote on Facebook.

Ms. Cooper joined the daytime serial six months after its March 1973 debut, staking claim to the title of longest-tenured cast member. The role earned her 11 Daytime Emmy nominations and a trophy for best actress in 2008.

As the years passed, Ms. Cooper brushed aside thoughts of saying goodbye to the show. "What would I do? I'm no good at crocheting. My fingers would bleed," she told the AP as she turned 83 in October.

She was born in Taft, Calif., in 1928, attended the College of the Pacific, and performed in local productions before her professional career began with the 1953 film The Redhead From Wyoming starring Maureen O'Hara. Other film credits include 1968's The Boston Strangler with Tony Curtis and 1967's Tony Rome with Frank Sinatra.

But it was her role on The Young and the Restless that made her a star.

In 1984, Ms. Cooper's real-life face-lift was televised on the show as her character underwent the surgery at the same time.

"To this day, people will come up to me and say: 'Thank you so much for doing that. My mom or I had something done,' and not just cosmetic surgery," she said. "That was an incredible experience in my life."

Her 30-year marriage to Harry Bernsen ended in divorce. The couple had three children and eight grandchildren.