The British royals have a long history of hazing newcomers — particularly women who are dating family members — and only those who are “tough as nails” tend to survive, said a cousin of King Charles III in an exclusive interview with The Post.

“To Meghan Markle, I say, ‘What you are going through is a hellish kind of hazing,’” said Christina Oxenberg, a descendant of Serbian royalty who counts King Charles III as a third cousin. “If she can just hang in there, someone else will come along who can take the heat. Nobody gets a pass.” Including, she added, Kate Middleton.

Oxenberg, 59, is a writer and fashion designer and the younger sister of actress Catherine Oxenberg. Their mother is Princess Elizabeth of Yugoslavia, who, Oxenberg said, was once very close to Charles.

Christina Oxenberg, a cousin of the British royal family, said that the family has "hazed" Meghan Markle — and mocked Kate Middleton in the past.
Christina Oxenberg, a cousin of the British royal family, said the family has “hazed” Meghan Markle — and mocked Kate Middleton in the past.
Christina Oxenberg says Meghan Markle simply needs to wait out her hazing by the royal family — because it will eventually move to someone else.
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The royal family thought it pretty funny that the British press labeled Middleton “Kate Middle Class,” Oxenberg said.
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Oxenberg, who has lived among the British royals most of her life, recalled the snobbery once whispered behind the new Princess of Wales’ back.

When Prince William, now the heir to the throne, was dating Middleton before their 2011 marriage, the royal family thought it pretty funny that the British press labeled her “Kate Middle Class,” Oxenberg said.

According to the Express, Camilla — now the queen consort — allegedly referred to Middleton’s parents, Carole and Michael, as “Meet the Fockers.”

Koo Stark dated Prince Andrew for 18 months in the early 1980s before his mother, Queen Elizabeth, put an end to the relationship.
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When Princess Michael of Kent, a baroness of Czech-German lineage, married into British royalty in 1978, the royals delighted in giving her a hard time.
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Christina Oxenberg, who counts King Charles III as a third cousin, said of newcomers to the British royal family: “Nobody gets a pass.”
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“They thought it was all very funny — Kate Middle Class and Sarah Ferguson and Koo Stark,” Oxenberg said. “They meant no disrespect; after all, she is the future queen of England.”

Stark, an American actress and photographer, dated Prince Andrew for 18 months in the early 1980s before his mother, Queen Elizabeth, put an end to the relationship. Although she initially liked Stark, who bought Andrew his first pair of blue jeans, the monarch quickly intervened once the British press unearthed the actress’s appearances in soft-core porn films, which made her an unlikely match for the prince.

“It was a very flimsy reason,” Oxenberg told The Post. “There’s a good example of how you can suffer as a royal for no good reason.”

Christina Oxenberg’s mother, Princess Elizabeth of Yugoslavia.
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“They were both really in love,” she added of Andrew and Stark. “They were soul mates, and he was prevented from marrying his soul mate. Had he married her, things would be different today.”

Andrew, who was married to Sarah Ferguson from 1986 to 1996, was entangled in a friendship with convicted pedophile Jeffrey Epstein — and in March, the prince settled with sexual-abuse accuser Virginia Roberts Giuffre, paying her a reported $12 million after she said she was forced to sleep with him three times when she was 17.

Oxenberg herself admitted she was a former confidante of British socialite Ghislaine Maxwell, who is appealing a 20-year sentence following her conviction for helping to procure young women and girls for Epstein.

Christina is the sister of actress Catherine Oxenberg (above).
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Among the other now-royals who received their share of hazing, Oxenberg said, was Princess Michael of Kent, née Marie Christine von Reibnitz, a baroness of Czech-German lineage.

When Prince Michael of Kent, a first cousin of Queen Elizabeth II, married von Reibnitz in 1978, British royals delighted in giving her a hard time, Oxenberg told The Post.

Princess Elizabeth of Yugoslavia (right) is Oxenberg’s mother and was once very close to Prince Charles.
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“She was treated the same way Meghan [has been] treated — with this mocking and lack of respect,” she said. “We always used to mock her because she kept referring to the royals as ‘delicious cousins.’ It [the hazing] was all done out of habit and not full of hatred and violent plotting. I was a witness.”

Oxenberg was 16 years old at the time, and going through her own tribulations with her mother, Princess Elizabeth of Yugoslavia, a second cousin to King Charles III. While still married to Howard Oxenberg, a dress manufacturer from New York, Princess Elizabeth became engaged to the actor Richard Burton, while he was between marriages to Elizabeth Taylor. (Burton and the princess never wed.)

With Meghan, who married Prince Harry in 2018, the hazing has been particularly brutal, according to Oxenberg. “They are tough, they are tough on foreigners,” she said. “It’s not about your skin color, it’s about being a foreigner.”

Princess Elizabeth (far right) is related to the royal family through her great-uncle Prince Andrew of Greece — who was the father-in-law of Queen Elizabeth (second from left).
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Still, she called Meghan’s treatment by both the British press — which is analyzing her every move, especially during Monday’s funeral of Queen Elizabeth — and some members of the royal family as nothing short of “treasonous.”

“She is Harry’s choice of wife,” Oxenberg said. “By their own metrics they have called it a class system. They came up with that system, [by which] you have to respect Harry’s choice.”