(LOS ANGELES) -- Jeanne Cooper, a longtime star of the CBS soap opera The Young and the Restless, died Wednesday morning. A cause of death has not been revealed.
Cooper, who had played matriarch Katherine Chancellor since joining The Young and the Restless in 1973, was 84.
Cooper's son, former L.A. Law actor Corbin Bernsen, made the announcement Wednesday on his Facebook page, writing, "My mother passed away this morning just a short time ago, peaceful with my sister by her side, in her sleep."
Bernsen said of his mother, "She has been a blaze her entire life, that beacon, that boxer I spoke of earlier. She went the full twelve rounds and by unanimous decision...won! And while her light finally gave into the wind that gives flight to all our journeys, there will always be a glimmer left behind by what she stood for."
Cooper received several Daytime Emmy nominations, with one victory, during her 40-year run on The Young and the Restless. She also garnered two Primetime Emmy nods, including one for her guest role as the mother of Bernsen's character on L.A. Law.
Bernsen had written on Facebook last month that his mother was battling an undisclosed illness.
Cooper had three children with her ex-husband, Harry Bernsen.
The Young and the Restless actor Melissa Claire Egan tweeted on Wednesday, "Heaven just gained one feisty angel. RIP the beautiful Jeanne Cooper."
A statement from Nina Tassler, president of CBS Entertainment, reads in part, "She was the longest-running cast member on daytime's #1 show, bringing indelible charm, class and talent to every episode."
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