Prince Harry worried one of Prince William and Kate Middleton’s children will end up like…

Prince Harry is wary that history could repeat itself when it comes to sibling rivalries within the royal family.

In an interview with The Telegraph’s Bryony Gordon, the Duke of Sussex said he had concerns for the children of Prince William and Kate Middleton and what the dynamic of the heir and the “spare” could mean for them in the future.

The Prince and Princess of Wales have three children: Prince George, 11, Princess Charlotte, 9, and Prince Louis, 6.

“Though William and I have talked about it once or twice, and he has made it very clear to me that his kids are not my responsibility, I still feel a responsibility knowing that out of those three children, at least one will end up like me, the ‘spare’,” Harry said. “And that hurts, that worries me.

Harry detailed how the labels heir and spare, which were used to reference William and himself growing up, had a damaging effect on their relationship in his memoir, released earlier in January.

In “Spare,” the Duke of Sussex wrote that the entire royal family would use the phrases as a shorthand for William and himself. He adds that he felt, due to the label of spare, as if he was “brought into the world in case something happened” to William.

“The Heir and the Spare — there was no judgment about it, but also no ambiguity. I was the shadow, the support, the Plan B,” Harry wrote. “I was summoned to provide backup, distraction, diversion and, if necessary, a spare part. Kidney, perhaps. Blood transfusion. Speck of bone marrow. This was all made explicitly clear to me from the start of life’s journey and regularly reinforced thereafter.”

Later in the memoir, Harry said that he suspected the “tired childhood dynamic” of the heir and the spare was rooted in the sibling rivalry between himself and William, even as they became adults. Examples Harry gave included when he claimed William ordered him to shave his beard “as the Heir speaking to the Spare” before his 2018 wedding to Meghan Markle.

He hated the idea of me enjoying a perk he’d been denied,” Harry wrote

Ultimately, sibling rivalries between members of the royal family are nothing new, Leslie Carroll, a royal historian and author of nine novels about royal history, told Insider. She said that the terms heir and spare had been used for decades, referencing Queen Elizabeth II and Princess Margaret as an example.

She also said that much of the tension between royal siblings came down to clashing egos and lack of freedom given to modern-day royal spares, rather than the terms themselves.

Citing examples from the War of the Roses and feudal Britain, Caroll said royal spares were given tasks and responsibilities, such as leading armies. Meanwhile, in modern times, spares like Harry haven’t been encouraged by the family to pursue their passions or hold any serious responsibilities.

The infantilization of Harry as the Spare, having to request permission to do everything,” Carroll told Insider, contributed to his “trauma.”

Kensington Palace and representatives for the Duke of Sussex did not immediately respond to requests for comment from Insider.