NAMED: New York Yankee's all-star short stop Derek Jeter hit a home run for his favorite cause -- the plight of children -- when he was named spokesperson of the Children's Hospital of New York on Monday, reports PEOPLE's Antoinette Coulton. Jeter, 27, accompanied by his parents and sister, greeted more than 50 children, some of whom were decked out in Yankee shirts and caps. Jeter also used the opportunity to announce a partnership between his five-year old charity, the Turn 2 Foundation, the Children's Hospital and New York's Public School 128 to provide stress management and physical fitness seminars for students and their parents . . . DIAGNOSED: Former South African President Nelson Mandela, 83, has prostate cancer, though his life is not threatened, his foundation announced Tuesday. He is expected to undergo seven weeks of radiation treatment and will not require chemotherapy or surgery . . . CELEBRATED: Veteran comic Milton Berle was honored with a 93rd birthday bash at the Beverly Hills Hotel on Sunday. Among the guests: James Coburn, Frances Fisher, Robert Wuhl, Sid Caesar, Ed McMahon (who played host), Red Buttons (who told jokes) and Andy Williams (who sang "Moon River"). Berle, who is currently battling colon cancer, told the crowd, "I'll see you next year."