Irish people have expressed shock at the latest tragedy to hit the Kennedy family. However, most declined to comment while there was still a chance that Mr Kennedy jnr, his wife and his sister-in-law could be found alive.
The Taoiseach, Mr Ahern, said: "Our thoughts are with the Kennedy family who have long and close ties with Ireland at this very trying time for all of them."
In Co Wexford, the fate of Mr Kennedy evoked sadness intermingled with memories of his visit to the county as a child. Many remembered the shy, innocent boy who came with his mother to visit the ancestral homestead in Dunganstown in 1967.
"He ran in from the farm saying there was electricity in the grass and all because he got stung by the nettles," recalled his Irish cousin, Mr Patrick Grennan, yesterday.
At 23, Grennan is too young to have met the son of the former US president but he remembers the stories of the visit related by his mother and aunt.
"Jackie Kennedy wanted him and his sister, Caroline, to see the land where their family came from. She visited the homestead and then sent the children back the next day, barefoot, to experience authentic farm life."
Today, the links forged in the 1960s between the Kennedy dynasty in the US and their cousins in Dunganstown remain strong. Mr Grennan said his distress at the disappearance of Mr Kennedy was widely felt throughout the county. "People just cannot understand how another tragedy like this could have happened to the family."
There were more visitors than usual yesterday to the John F Kennedy visitor centre in the village, and many of them took the opportunity to express their concern. Mr Grennan said the centre would close if Mr Kennedy's death was confirmed, but locals were still hoping that he might be alive.
In June 1997, Mr Kennedy came back to Ireland. He flew to Dublin and stayed in the Shelbourne Hotel.
While there, he interviewed the Sinn Fein leader, Mr Gerry Adams, for George, a glossy political magazine he began publishing the year before. He took the train to Belfast, where Sinn Fein's press officer, Mr Richard Macauley, showed him around the city.
However, it was his attendance at the funeral in Co Laois of Patrick Kelly, an IRA member convicted in the UK of a bomb plot against Princess Anne, which provoked most controversy. Kelly was released from prison when suffering the final stages of skin cancer.
His presence was criticised by Dr Ian Paisley, who said that most people would "gag" at the idea of Mr Kennedy lending his "assumed prestige" to Kelly. A spokeswoman for George said Mr Kennedy was working on a story for the magazine.
The following month, an invitation to a social function held in New York to celebrate the visit of the newly-elected British Prime Minister, Mr Tony Blair, was withdrawn.
