(CNN) -- Jeanne Cooper, who played Katherine Chancellor, the "Dame of Genoa City," on "The Young and the Restless," has died. She was 84. Her death was confirmed by her son, actor Corbin Bernsen, on his Twitter account. "Mom passed this morning," Bernsen posted. "She was in peace and without fear." Cooper had been suffering from an undisclosed illness. The cause of death was not given. Cooper was already a well-established TV actress when she took the role of Chancellor in 1973. "The Young and the Restless" was struggling in the ratings and its creator, William J. Bell, wanted to spice things up.
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Jeanne Cooper played Katherine Chancellor on "Young and the Restless"
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Cooper played role for 39 years
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Actress is mother of actor Corbin Bernsen
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"She was in peace and without fear," Bernsen tweeted
"When you did work you were proud of, you'd hope for approval or a 'good job' from @placeholder as a child would from a parent.