More than 250 guests, most of them members of the Kennedy clan, had been expected at yesterday afternoon's wedding in the grounds of the family compound on the southern shore of Cape Cod. The previous evening, Ethel Kennedy, widow of the late Senator Robert Kennedy, had held a bridal dinner for her daughter, Rory.
John F Kennedy jr, 38, cousin of the bride and only son of the assassinated president, had been due to arrive at the Hyannisport estate yesterday, after spending Friday night en route at the island of Martha's Vineyard. But he and his wife, Carolyn, 33, flying from New Jersey, never reached the island.
When the news first broke that JFK's small plane was missing off the coast of Long Island, a shudder went through the east coast political and media establishment. Could it really be that the "curse" had struck again, felling another Kennedy in his prime? His father, John F Kennedy, had met his premature death at the hands of an assassin in Dallas in 1963. His uncle, Robert, who aspired to follow in his brother's footsteps, was assassinated five years later.
Yesterday's news was replete with eerie coincidences. Friday was the 30th anniversary of an earlier Kennedy tragedy, the death of Mary-Jo Kopechne at Chappaquiddick, in a car driven by President Kennedy's brother, Ted. Yesterday, too, as ships and helicopters searched the waters north of Long Island, relatives of some of the 230 people killed in the unexplained crash of TWA's flight 800 were gathering on the island's southern shore to commemorate the third anniversary of that disaster.
But it was the jinx that has turned rejoicing into weeping so often in the Kennedy family in the past to which commentators returned again and again in the hours of waiting for the definitive news yesterday.
John Kennedy jr, who is universally recalled in the US from the pictures of himself and his sister Caroline as small children at his father's funeral, shone out in many ways as a laudable exception in a clan plagued by scandals and rumours of every hue, from drink, drugs and sex, all the way to allegations of murder surrounding one young relative. The last Kennedy to meet an untimely death was Michael, a son of Robert Kennedy, killed after hitting a tree while skiing in Aspen in 1997. He had just surfaced from reports - never denied - that he had an illicit affair with an under-age babysitter. The girl refused to testify against him, but his wife left him. Michael's elder brother, Joe Kennedy, a Congressman, abandoned his Congressional career in the aftermath.
Arguably, though, he was already unelectable to the post he aspired to - governor of Massachusetts, after accusations by his wife, Sheila, in a furious book that he had wangled an "annulment" from the Vatican to avoid the ignominy of divorce. Joe had also had his own "Chappaquiddick" in 1973, when a woman passenger in his Jeep was paralysed after an accident. Joe's brother, David, was found dead from a heroin overdose in a Palm Beach hotel room at the age of 29.
JFK jr had eschewed the political and public service careers pursued by so many of his relatives, and - despite living a glitzy Manhattan life - dissociated himself from the fast living and rakish exploits of others. When the babysitter scandal broke over his cousin Michael, John used an article in George magazine, his own publishing venture, to describe his relative as a "poster boy for bad behaviour" and remind the "clan" that "of those to whom much is given, much is expected".
George, with its uneasy mix of style and politics, may not have been the pioneering success he had hoped it would be, but it put a Kennedy into the circles of media power and influence that revolve around Manhattan, and reinforced the family's continuing place in American political life.
To that family, the presumed death of JFK jr - who had no children - is not just another member lost to the "curse". It is the end, in a way, of the JFK legend. However many other Kennedy scions succeed in American politics - and Robert Kennedy's daughter, Kathleen Kennedy Townsend, seems to have a promising future - there will be no son or daughter to claim the political legacy of JFK and bear his name.
Fittingly, perhaps, if grimly, this is how Camelot has ended: in the black waters of the Atlantic, at night.