Prince William was allegedly "wounded" when Prince Harry seemingly questioned his choice for a wife, according to a royal biographer.

The Prince of Wales, Princess of Wales and Duke of Sussex were very close before the latter met and married Meghan Markle. The three royals were even dubbed the royal trio. However, royal biographer Robert Hardman, a British journalist, author and documentary filmmaker, has claimed that Prince Harry seemingly criticized his big brother for marrying Middleton.

Prince Harry and Kate Middleton
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Prince Harry and Kate Middleton leave the church after the Royal wedding of Zara Phillips and Mike Tindall at Canongate Kirk on July 30, 2011 in Edinburgh, Scotland.

"Harry talks about marrying someone for love, not because it's the sort of person you ought to," Hardman told The Post. "I think that's a lot more wounding. I mean, that's effectively dissing your brother and his choice of wife in a very public way."

Hardman was referring to a statement Prince Harry made in his and Markle's Netflix documentary "Harry & Meghan." In the first episode, Prince Harry spoke about how the men in the royal family chose their brides not out of love but responsibility, suggesting that they had to pick someone who fit the mold of the monarchy.

Prince William, Prince Harry and Kate Middleton
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Prince William, Prince Harry and Kate Middleton smile as they take part in 'welly wanging', with children and representatives from charities and Aardman Animations, during a meeting of the Charities Forum at BAFTA on October 26, 2015 in London, United Kingdom.

"For so many people in the family, especially obviously the men, there can be a temptation or urge to marry someone who fits in the mold, as opposed to somebody who you are perhaps destined to be with," Prince Harry said.

"The difference between making decisions with your head, or your heart. And my mum [Diana] made most of her decisions, if not all of them, from her heart. And I am my mother's son."

Aside from seemingly dissing the heir to the throne's choice of wife, Hardman pointed out that the royal siblings' feud worsened due to Prince Harry's memoir "Spare," where he detailed their childhood, physical altercation and the tension between their wives in the run-up to his and Markle's royal wedding in 2018.

Prince Harry and Kate Middleton
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Prince Harry and Kate Middleton arrive to attend a service of commemoration and thanksgiving to mark Anzac Day in Westminster Abbey in London on April 25, 2019.

"Both these brothers, they've guarded their privacy," the royal commentator added. "It's been really important to them. And William is a really private person. He doesn't do nearly as many interviews as his father did at this age, and family life is absolutely off-limits for media. Privacy is really important, and Harry's just gone and chucked all these stories about their childhood into the public domain."

Hardman previously spoke with insiders, palace staffers and some royal family members for his upcoming biography, "Charles III: New King, New Court. The Inside Story." Insiders reportedly told him the Queen was livid when Prince Harry and Markle announced their daughter's name.

Kate Middleton, Prince William, Prince Harry and Meghan Markle
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Kate Middleton, Prince William, Prince Harry and Meghan Markle on the long Walk at Windsor Castle on September 10, 2022 in Windsor, England.

A report from the BBC, citing an unnamed source, claimed the Sussexes did not ask for the Queen's permission to name their daughter "Lilibet," but the royal couple denied this.

Meanwhile, royal pundit Lady Colin Campbell said the Sussexes reached out to the Queen to use her name, and she approved, but the latter thought they would use "Elizabeth" and not her nickname "Lilibet."