American Socialite, Sister of 35th US President John F. Kennedy, and Marchioness of Hartington. The fourth child and second daughter of wealthy businessman Joseph Patrick Kennedy and socialite Rose Fitzgerald Kennedy, she was born into a life of privilege. Nicknamed "Kick" due to her irrepressible nature, she received a private education at the Riverdale Country School in the Bronx borough of New York City, New York and later the Convent of the Sacred Heart in Noroton, Connecticut, and the Holy Child Convent in Neuilly, France. In 1938 she accompanied her family to England when her father was appointed US Ambassador there, and she continued her education at Queen's College in London. When World War II broke out in September 1939, she returned with her family to the US, except for her father. She then attended the Finch School in the Manhattan borough of New York City and Florida Commercial College, all while working as a volunteer for the Red Cross. In 1941 she left school to work as a research assistant for Frank Waldrop, the executive editor of the Washington Times-Herald. Two years later, she returned to England and worked at a Red Cross servicemen center, and started a romantic relationship with William Cavendish, the Marquis of Hartington and heir apparent of the Duke of Devonshire; in spite of her parents' strenuous objections, they were married in a civil ceremony in Westminster, London, England on May 6, 1944. Her oldest brother, Joseph P. Kennedy, Jr., who was stationed in England with the US Army Air Corps, was the only Kennedy family member to attend. About a month later, her husband left for military service in Europe as a major with the Coldstream Guards Armoured Division of the British Army. He was killed by a sniper's bullet near Heppen, Belgium on September 10, 1944. She developed a romantic relationship two years later with British aristocrat Earl Fitzwilliam, who was in the process of divorcing his wife. Again, her mother objected to her choice and threatened to cut her off from the family if she continued the relationship. In May 1948 she learned that her father would be in Paris, France and she decided to fly there in an attempt to gain his approval of her marriage to Fitzwilliam. Afterwards, she and Fitzwilliam decided to fly to the French Rivera for a vacation. During the flight, the small aircraft encountered strong turbulence that inflicted severe damage and it crashed, killing everyone on board. Her father was the only Kennedy family member who attended her funeral. Three years later, her younger brother Robert F. Kennedy named his oldest daughter Kathleen in her honor.