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President Obama, along with the First Lady, led a rousing rendition of "Happy Birthday" to Sen. Ted Kennedy, at a star-studded 77th-birthday tribute to the political legend at Kennedy Center on Sunday night.
Among the stars who performed at the celebration were comedian Bill Cosby, actresses Lauren Bacall and Bernadette Peters, singer James Taylor and conductor John Williams.
Kennedy has been getting treatment for brain cancer in Florida - he was diagnosed with a malignant brain tumor after suffering a seizure last May.
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Barack and Michelle Obama celebrate Ted Kennedy's 77th birthday at the Kennedy Center on Sunday night.
Obama leads the singing of "Happy Birthday," alongside singer James Taylor.
Greeting comedian Bill Cosby, alongside Lizz Wright and Denyce Graves.
The First Lady greets Senator Kennedy and his wife, Victoria, as Senator John Kerry listens.
The AP reports:
Toward the end of the gala, Cosby introduced Obama to loud applause from the performers and the audience. The president strode to the center of the stage and then conducted the performers in the birthday tune. Kennedy stood and delivered a thumbs-up from his balcony, where he was accompanied by first lady Michelle Obama.
The president later met Kennedy in his box as the performers sang "The Best Is Yet to Come."
Kennedy's niece, Caroline, also honored her uncle, making light of her short-lived attempt to take former Senator Hillary Clinton's New York Senate seat:
"I never thought I'd be in a room with so many senators."