Prince William, Prince Harry’s ‘devastating breakdown’ revealed in new book: ‘I have been astonished’

Royal author Robert Lacey says he has been “astonished” by what he has uncovered for his upcoming book on Princes William and Harry.

The author, who also serves as historical consultant to the hit Netflix series “The Crown,” is releasing a new book in October titled “Battle of Brothers: William and Harry –­ The Friendship and the Feuds,” which addresses "the unique and complex relationship at the heart of the royal family’s recent woes,” People magazine reported on Monday.

The book will also put the two brothers' relationship into a historical context, exploring how the “heir” and the “spare” have impacted the British monarchy over the years.

“Much reported on but little understood, Diana’s boys have lived under constant scrutiny since birth,” reads the book’s synopsis, as revealed by the outlet.

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“Raised to be the closest of brothers, the last 18 months have been a devastating breakdown of their once unbreakable bond,” it continued. “With an unrivaled knowledge of court life and access to impeccable sources, Robert Lacey investigates the untold reality of the brothers’ relationship, explaining what happened when two sons were raised for vastly different futures and showing how the seeds of damage were sown as their parents’ marriage unraveled.”

According to the outlet, the book also looks into how the relationship between the siblings has been impacted by their wives Kate Middleton and Meghan Markle, as well as why Harry decided to step back as a senior royal alongside Markle and move to Los Angeles with their son Archie.

“I have been astonished and sometimes moved to tears by the fresh details and insights I have discovered in researching this story of family conflict,” Lacey said in a press release. “It has been both enthralling and painful to trace this drama through the memories of close witnesses and some of the people most intimately involved.”

“These two brothers –­ once inseparable and now separated by much more than mere distance –­ have been acting out the contradictions that go back into their childhoods and even before that: into their parents’ ill-fated marriage,” he continued. “We have seen conflicts between heir and spare in every recent generation of the royal family — but nothing so profound as this.”

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Britain's Prince Harry and older brother Prince William.

Britain's Prince Harry and older brother Prince William. (Tolga Akmen - WPA Pool / Getty Images)

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Rumors of an alleged royal feud came to light in 2019, when British bestselling author Katie Nicholl claimed that since Markle, 38 and Harry, 35 announced their engagement in 2017, William, 38, grew increasingly worried for his brother and his whirlwind romance with the American actress.

“William was quite concerned that the relationship had moved so quickly,” Nicholl claimed in the TLC documentary “Kate V. Meghan: Princesses at War?”. “And being close to Harry, you know, probably the only person close enough to say to Harry, ‘This seems to be moving quickly. Are you sure?’ And I think what was meant as well intended brotherly advice just riled Harry.”

“Harry is hugely protective of Meghan,” Nicholl continued. “He saw that as criticism, he interpreted that as his brother not really being behind this marriage, this union. And I don’t think things have been quite right ever since.”

Harry hinted at an alleged rift with his older brother in last year’s ITV documentary “Harry & Meghan: An African Journey.”

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“Part of this role and part of this job, this family, being under the pressure that it’s under, inevitably stuff happens,” he said at the time. “But look, we’re brothers, we’ll always be brothers. We’re certainly on different paths at the moment but I’ll always be there for him and I know he’ll always be there for me.”