U.S. Sen. Edward Kennedy has a malignant brain tumour, his doctors said on Tuesday.
Here are some facts about the 76-year-old Massachusetts Democrat.
* First elected in 1962, he is the second-longest serving member in the current U.S. Senate, and has served longer than all but two other senators in American history.
* He is the last surviving of four Kennedy brothers, including President John Kennedy, who was assassinated in 1963, and Robert Kennedy, who was assassinated in 1968 during his presidential bid. Both brothers also served in the U.S. Senate.
* Edward Kennedy's one try for the White House ended in failure in 1980, when he took on a sitting president of his own party, Jimmy Carter. His presidential ambitions were haunted by an accident at the Massachusetts island of Chappaquiddick in 1969, when his car plunged off a bridge and a young woman riding with him, Mary Jo Kopechne, drowned.
* Known as "Teddy," he is a liberal icon, but also is known as a consummate dealmaker, able to reach across party lines to get things done. He is chairman of the Senate Health, Education, Labor and Pensions Committee, and serves on the Judiciary and Armed Services Committees.
* Kennedy became involved in the 2008 presidential race by endorsing Illinois Sen. Barack Obama for the Democratic nomination. Many political observers saw this as a passing of the torch from the old Democratic past to the future generation.
* He is the father of U.S. Rep. Patrick Kennedy of Rhode Island and has two other children from his marriage to Joan Bennett Kennedy, which ended in divorce. He took on the role of surrogate father to his slain brothers' 13 children. He married Victoria Reggie in 1992.
* His father Joseph Kennedy was appointed ambassador to Britain from 1938 to 1940, and was instrumental in advancing the political careers of his sons.
* One of his more famous statements came in his eulogy to his brother Robert. "My brother need not be idealized, or enlarged in death beyond what he was in life. He should be remembered simply as a good and decent man, who saw wrong and tried to right it, saw suffering and tried to heal it, saw war and tried to stop it."