Prince William, Kate Middleton 'Terrified' Of Harry, Meghan's International Trips; Duchess Thinks She's Right About Royals, Expert Claims

Prince William and Kate Middleton couldn't compete with Prince Harry and Meghan Markle when it comes to their "mini royal tour" amid the Princess of Wales' cancer battle, according to royal experts.

The Prince and Princess of Wales were reportedly bothered by the Duke and Duchess of Sussex making international trips and being treated as royals overseas when they had already quit their duties years ago. There are rumors that Prince Harry and Markle are making another trip abroad, and this allegedly leaves Prince William and Middleton "terrified."

"The senior royals, especially William and Kate, are terrified of one thing above all others: that Harry and Meghan will continue to organize trips across the world until they are seen as the public face of the royal family," Tom Quinn, royal biographer and commentator, told the Mirror.

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"The fear is made worse because William knows that with his wife stricken with cancer, he cannot compete, and he can't stop the Meghan and Harry rollercoaster."

While Prince William is allegedly worried about the Sussexes continuing their visit to foreign countries, which many dubbed as a "mini royal trip," his sister-in-law is reportedly feeling that she's right about her opinion of the royal family. Quinn said in another interview with the same outlet that the former actress was pleased with "being treated as a great figure" during their recent trip to the African nation, and it was reportedly proof the British monarchy should have supported them as part-time royals.

"Meghan sees her visit to Nigeria as a huge success and proof that she was right all along -- she and Harry should have been allowed to be part-time royals because they are really good at it," Quinn claimed.

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The author of "Kensington Palace: An Intimate Memoir from Queen Mary to Meghan Markle" also pointed out Markle's disposition during the trip. She reportedly looked delighted during the three-day trip to Nigeria, but her husband appeared "unsure" about it.

"Meghan's face during the Nigeria tour said it all. Her pleasure in being treated as a great figure was unmistakable," Quinn said.

"Harry, on the other hand, often looked unsure of himself; he had that unconfident, slightly sad-little-boy look -- the look of someone asked to do something he was never quite sure of by his more confident partner. Swept up by his wife's confidence it may never have occurred to Harry that playing at being on an official Royal tour to Nigeria just makes his brother and his father, King Charles, even more furious with him and even more determined to push him away."

Quinn previously said that the British monarch and heir apparent were upset about the Sussexes' visit to Nigeria. Prince William was reportedly "furious," and King Charles was "angrier than anyone has ever seen him." The father and son reportedly felt that Prince Harry and Markle wouldn't accept they were no longer working royals.

"William and his father, King Charles, don't like it one bit," Quinn said. "For Charles and William, it's as if Meghan and Harry are saying, 'We don't need your permission to be working royals -- we will do it on our own terms whenever and wherever we like.'"