The chance of a reconciliation between Prince William and Prince Harry reportedly seems unlikely, despite their united front following the death of their grandmother, Queen Elizabeth.

The Duke of Wales “simply can’t forgive” his brother Harry for his actions over the last few years, according to Katie Nicholl, author of The New Royals – Queen Elizabeth’s Legacy and the Future of the Crown, who spoke about the future relationship between the two brothers while appearing on “Dan Wootton Tonight”.

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“William simply can’t forgive [Harry], not just for his behaviour and what he’s done and how he’s done it, but look at how much now rests on William,” Nicholl’s said.

“He always thought Harry would be his wingman, now he’s doing it on his own. Thank goodness he’s got Kate by his side,” the author added.

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Nicholl’s upcoming book examines how Prince Harry and Meghan Markle’s relationship with members of the royal family continues to escalate following the Sussexes’ decision to step down as senior royals and move to the U.S.

She claims that William and wife, Kate Middleton, felt “relief” when Harry and Meghan revealed they’d be moving away, ultimately feeling as though the “drama was gone.”

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As for the Queen, Nicholl says she was “hurt and exhausted” by the Sussexes’ decision.

“[The Queen] was very hurt and told me, ‘I don’t know, I don’t care, and I don’t want to think about it anymore’,” a source close to the late monarch told Nicholl, which was previously revealed in an extract of the book published by Vanity Fair

The source added that Harry and Meghan’s move was more of a regret and disappointment to the Queen because she wasn’t able to spend as much time with her great-grandchildren, Archie and Lilibet.