How a Member of the Kennedy Family Defied Her Parents and Became a British Noble

It can be easy to forget that within the so-called “Kennedy Curse” and the tragic deaths of President John F. Kennedy and Robert F. Kennedy are the losses of other family members, some nearly forgotten by history.

Such is the case with Kathleen Kennedy. She was the fourth-eldest child and second daughter of Joseph P. Kennedy Sr. and his wife, Rose, and went by the nickname “Kick.”

Born in 1920, sandwiched in between sisters Rosemary and Eunice and three years younger than JFK, Kick became “the only rebel of the family,” according to Kennedy biographer Lynne McTaggart.

“If you look at all nine [Kennedy] children, she was the only one who didn’t march down the prescribed road,” McTaggart, author of the 1983 biography Kathleen Kennedy: Her Life and Times, told the New York Post.

In her early years, Kick’s mother kept her daughter in check by sending her to an all-girls school in a somber Connecticut convent. But when she turned 18, her father became the U.S. ambassador to the United Kingdom and took his family overseas, where Kick was an instant hit.

Kennedy biographers love to claim that Kick was no great beauty, but she found her own ways to stand out amongst the English debutantes.

“She did not hang back shyly or demurely,” wrote Barbara Leaming in her 2016 biography, Kick Kennedy: The Charmed Life and Tragic Death of the Favorite Kennedy Daughter. “The newcomer was willing to laugh at herself — her mistakes, her gaucheries and even her physical flaws — in a way that was simply unknown among English girls.”

In the 2016 Smithsonian Channel docuseries Million Dollar American Princesses, Robert F. Kennedy Jr.’s daughter Kick Kennedy — who was named after her great-aunt — reflected on the eccentric nature of her namesake.

“She was idiosyncratically charming,” the younger Kick shared. “She would call the Duke of Marlborough ‘Dukie Wookie’ and chewed gum walking down the streets of London.”

Kick and Rosemary made their royal debut in 1937, and not long after, she met William Cavendish, the Marquess of Hartington and future Duke of Devonshire. Kick affectionally called him “Billy.” He was soft-spoken where she was boisterous, and they’d been raised in different, but equally posh, worlds.

But the most striking difference was that Billy was Protestant. For the devout Catholic Kennedys, this was a non-negotiable. Kick pleaded with her parents to accept their relationship, but was ultimately forced to return to America when the Nazis invaded Poland in 1939, signaling the start of World War II.

She continued to pine for Billy and, in 1943, eventually found her way back to him by volunteering with the Red Cross. In May 1944, the couple tied the knot in a civil ceremony — a mortal sin in the eyes of the Kennedys, especially matriarch Rose. Kick’s eldest brother, Joe Jr., who was stationed in Britain with the U.S. Navy, was the only member of the family to attend.

Tragedy soon followed bliss. Four weeks after they were married, Billy was sent to the Belgian front. In August, Joe Jr. was killed when his plane exploded during a secret bombing mission over France. A month later, Billy was also dead, gunned down in Belgium by a German sniper.

“I can’t imagine anything more devastating,” the modern-day Kick said of her great-aunt in Million Dollar American Princesses. “But the rule is, Kennedys don’t cry.”

In the aftermath of the war, Kick found love again with another nobleman. Peter Fitzwilliam, the 8th Earl Fitzwilliam, who was in the process of divorcing his first wife when they began their romance. Like the Marquess, he was also a Protestant. Like Kick’s first marriage, this romance also incensed Rose to the point of shunning her once-favored daughter.

In McTaggart’s opinion, the eyebrow-raising relationship was a result of both Kick’s rebellious nature and a bit of post-war recklessness.

“When you’ve seen so much tragedy during the war, it makes you feel that you’d better live for the moment,” the biographer said. “Fitzwilliam had a lot of money and was a lot of fun.”

Once his divorce was final, Kick and Fitzwilliam boarded a flight to France to ask for her father’s blessing. Despite inclement weather on May 13, 1948, their plane pushed on — and crashed in Saint-Bauzile, Ardèche, in southern France.

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In a tragic bookend of her wedding, only Joseph Kennedy Sr. attended Kick’s funeral, so as to keep her scandal apart from the family’s growing political power in the U.S.

“She was the star of the family, and it left them, particularly her mother, with terrible, unresolved agony over a relationship with the child that was closest to her,” Leaming wrote. “Her mother was left with something that was so unresolved — that she didn’t go to her daughter’s funeral, she didn’t bring the body back here to bury her.”

Kick was buried in a small churchyard in Edensor, England, with a headstone that identifies her as “Kathleen Cavendish, Marchioness of Hartington.”

While her husband was buried in Belgium, a plaque in front of the worn stone commemorates another important man in her life, who visited in the final months of his own.

It reads, “In memory of John F. Kennedy, President of the United States, who visited this grave 29 June 1963.”