Yesterday's announcement of Prince Harry's memoir reportedly sent shockwaves through the Royal Family, sparking concerns that the Duke of Sussex could drop further bombshell revelations about his royal relatives. A royal source told Us Weekly that the book detail has particularly alarmed both Prince Charles and Prince William.

       Us Weekly reported that an insider source had said, "The Royal Family is shaken up about the book."

       "Prince Charles and Prince William are particularly concerned about what Harry will reveal."

       "Harry's recent streak of criticisms was bad enough already."

       Relations between the three have been tense since Prince Harry and Meghan Markle announced their intention to step away from the Royal Family in January 2020.

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       During the couple's tell-al interview with Oprah Winfrey in March, Prince Harry characterised his relationship with William as "space" and said they were "on different paths".

       He said his father had "stopped taking my calls" and said he felt "really let down" by the Prince of Wales' response to the situation.

       He also claimed that his father and brother were "trapped" within the institution.

       The interview was a PR disaster for Buckingham Palace, as the Duke and Duchess claimed that an unnamed member of the Royal Family had made a racist remark and the couple's mental health had been ignored by the family and Palace aides.

       Prince Harry announced that he would be publishing "an intimate and heartfelt memoir" through Penguin Random House.

       The memoir is expected to cover the Prince's childhood and time as a working royal, as well as his military career and role as a father and husband.

       In a statement, the Duke said "I’m writing this not as the prince I was born but as the man I have become."

       "I’ve worn many hats over the years, both literally and figuratively, and my hope is that in telling my story – the highs and lows, the mistakes, the lessons learned – I can help show that no matter where we come from, we have more in common than we think."

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       The book is due to be published in late 2022 with all proceeds donated to charity.

       Penguin Random House branded the Prince as "one of the most fascinating and influential global figures of our time".

       They stated, "Prince Harry will offer an honest and captivating personal portrait, one that shows readers that behind everything they think they know lies an inspiring, courageous, and uplifting human story."

       Whilst the details of the book deal have not been made public, it is believed that the Prince received an advance of $20million in US dollars.

       The book will be published in both digital and print formats and will be available on audiobook.