The Fitzgeralds, whose name is now among the most recognizable of middle initials, were at the heart of a celebration of the JFK visit's anniversary over the weekend.
President Kennedy's daughter, Caroline, led a family pilgrimage to Bruff, where Tom Fitzgerald was born in 1823, to honor the "better half of the family."
Caroline Kennedy, along with her husband, Edward Schlossberg, their three children, and her cousin Sydney Lawford, stopped by the church of St. Peter and St. Paul, examined old family records and said prayers of remembrance.
And in New Ross, where the president's great-grandfather Patrick departed Ireland in 1848, a day-long street party culminated in the lighting of an eternal flame.
A lamp carrying the flame from Kennedy's grave at Arlington National Ceremony in Virginia was flown to Dublin and then brought by an Irish naval ship to New Ross, where it was used to light the torch.
"May it be a symbol of the fire in the Irish heart, imagination and soul," Caroline Kennedy said, before a crowd of more than 10,000 people.
Caroline Kennedy's 20-year-old son, Jack, spoke about his hopes for following his grandfather into politics.
"We have been told over and over that America is no longer the great country that it was when my grandfather was president," he said. But despite facing a "series of problems that previous generations refused to address," Jack Kennedy said optimism still has a place in the 21st century.
"The glow from this flame can truly light the world," he said.