The Kennedy family holds a unique place in American history for its tradition of public service, glamor and considerable tragedy.
One generation of the family has now seen three of its men serve and die in public office.
The Kennedy clan of parents Rose and Joe Kenndey Sr. were third generation Irish-Americans, boasting nine children born over the space of 17 years -- Joe Jr., John, Rosemary, Kathleen, Eunice, Patricia, Robert and Jean. The youngest and fourth son was Edward, who would come to be known as Ted.
Raising their children in a Boston of Brahmins descending from English, they were determined that their sons and daughters would break through the social barriers that limited Irish expectations and impressed upon their children the themes of religious devotion and social responsibility.
Joe Kennedy was a successful businessman and proud father who wanted one of his sons to grow up to be president of the United States. His first choice was his oldest son, Joe, Jr. While serving in World War II, Joe Jr. was killed in a bombing run over France in 1942. This was the first of many tragedies the Kennedys would suffer. Kathleen Kennedy died in a plane crash at the age of 28 and Rosemary lived most of her life in an institution.
The political gene started on Rose Kennedy's side, with her father "Honey Fitz" Fitzgerald, the first Irish-American mayor of Boston.
"Honey Fitz knew that the way to build a political coalition was to go from bar to barbershop to street corner and really get to know the people," said Peter Cannelos of the Boston Globe, editor of "Last Lion: The Fall and Rise of Ted Kennedy." "By the time Ted was entering his teens, Honey Fitz, who still knew everybody on every street corner, would take Teddy with him as he chatted just with average people. And I think it made a deep impression on Ted."
But it was John Kennedy, the oldest surviving brother, who first entered politics, at his father's urging. He won a congressional seat in 1947, then successfully ran for Senate in 1952. In 1960, after a bruising campaign against Richard Nixon, Kennedy was elected the first Catholic president of the United States.
His inaugural address signaled a new era in politics.
"Let the word go forth from this time and place, to friend and foe alike, that the torch has been passed to a new generation of Americans born in this century," he said on Jan. 20, 1961.
John Kennedy would serve as president for just 1,000 days before his assassination in Dallas on Nov. 22, 1963.
His younger brother Robert Kennedy served as his attorney general and in 1964 won a seat in the Senate.
During his campaign for president just four years later, Robert Kennedy was gunned down in Los Angeles, June 5, 1968.
The assassination of a second brother was almost too much for Ted Kennedy, who was then serving in his second term in the Senate.
"He seriously contemplated getting out of politics after Robert's death," said Adam Clymer, author of a biography of Kennedy. "He thought, you know, it might just be too much. He might be too obviously the next target and all of that. But he decided to stick it out and as he said on more than one occasion, pick up a fallen standard."
Ted Kennedy went on to serve in the Senate for 47 years.