Jean Kennedy Smith, sister of former US president John F Kennedy, passed away on Wednesday at her home in Manhattan; she was 92.
Her death was confirmed by her daughter Kym, reports the New York Times.
She served as the United States ambassador to Ireland in the 1990s and helped pave the way for a formal agreement to end decades of sectarian violence in Northern Ireland.
Smith was the youngest and last-surviving sibling in a family that embedded itself in the American consciousness and wrote itself into American history, producing a president and senators and an unrivaled mystique fashioned out of political glory, personal charisma, great wealth and staggering tragedy.
Until the age when most people retire, Smith led a quiet life of privilege and philanthropy, with palatial homes, summers at the shore and a busy calendar of society and charity functions.
She shared family triumphs and tragedies, though always in the shadow of her siblings, including President John F Kennedy, Senators Robert F Kennedy and Edward M. Kennedy, Eunice Shriver and Patricia Kennedy Lawford.
But in 1993, when she was 65, a doyenne of charity balls and the widow of Stephen E Smith, the Kennedy family's troubleshooter and financial adviser.
Jane Kennedy Smith was named ambassador to Dublin by President Bill Clinton at the behest of her brother Teddy. But he had no illusions about her appointment.