Helmut Sonnenfeldt, 86, a confidant and top adviser to former secretary of state Henry Kissinger who was credited with helping formulate the Nixon administration's policy of detente with the Soviet Union, died Sunday in Chevy Chase, Md. He had Alzheimer's disease, said his wife, Marjorie.

He was known among insiders as "Kissinger's Kissinger," a moniker that reflected the deep philosophical affinity he shared with his boss despite what both men described as an often-rivalrous relationship. They met shortly after World War II during service in the U.S. Army in their native Germany. Both of Jewish origin, they had fled their homeland during the Nazi rise to power.

Few doubted Sonnenfeldt's importance, but because he was behind the scenes his influence was not usually visible to the public eye. In 1973, The New York Times called him "one of the least known men in the Nixon administration."

Phoebe Hearst Cooke, 85, who was a granddaughter of publishing tycoon William Randolph Hearst and used one of the nation's biggest fortunes to support a variety of philanthropic causes, has died.

Cooke, who had pneumonia, died Sunday in a Templeton, Calif., hospital, said the Hearst Corp., the media company she served as a director for 36 years. Her twin brother, George Randolph Hearst Jr., who was a former publisher of the Los Angeles Herald Examiner, died in June after a stroke.

A fixture on the Forbes list of the 400 wealthiest Americans, Cooke had personal assets recently estimated by the magazine at $1.9 billion. Although her flamboyant grandfather built a newspaper dynasty, Cooke was not a particularly public figure. She was best known as a rancher who gave extensively to equestrian organizations.

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