A new memoir indicated that the once resilient bond between Prince William and Prince Harry has been going through a devastating rift for the past 18 months. It is reportedly the most profound rift between an heir and a spare.

Slated to be released in October, was penned by "Battle of Brothers: William and Harry - the Friendship and the Feuds."

Ahead of Prince Harry and Meghan Markle's renouncement of senior membership in the royal family in early 2020 and upon relocating to Canada, the Duke of Sussex alluded to the tension between himself and his royal brother, reported Mirror.

The forthcoming book claimed that Prince William and Prince Harry's relationship began to aggravate 2 years ago.

Royal historian Lacey revealed that he was moved to tears while researching for the new memoir, according to MSN.

The unreleased book will chronicle the royal siblings' complicated relationship and the roles Kate Middleton and Meghan Markle, their wives, played in their rift.

Meanwhile, royal aides are concerned and bracing privately in case Prince Harry and Markle's memoir will depict Prince William as the antagonist in the conflict and the Sussex's renouncement of royal duties, reported The Sun.

According to a source, they are concerned that the 38-year-old future king could be painted as "unsympathetic, unfeeling and unsupportive" towards the Duke and Duchess of Sussex when they stepped down as senior working royals and chose financial independence.

Basically, the two brothers faced a dire breakdown of their former unbreakable bond.

Also Read: Prince William Gradually Becoming Blind? Duke Says His Eye Sight is "Just a Blur" 

Lacey, Historical Consultant for The Crown on Netflix is set forth to reveal that the "seeds were sown" following the separation of their parents, Prince Charles and Princess Diana.

Prince Harry and Markle publicly declared their stunning decision in early 2020 via Instagram.

The Sussexes resided in Canada for a short duration, with son Archie Harrison, then relocated to Los Angeles which is the Duchess of Sussex's hometown.

Lacey pointed out that the divide initially occurred in the two siblings' relationship as children due to the fact that both were "raised for vastly different futures" by their parents. He noted that they are currently divided beyond the mere distance.

Lacey further continued that it was fascinating and painful to trace the said drama through conversations with people closely associated with the British royal family.

"This dispute between brothers ranks alongside the abdication of King Edward VIII in its impact upon the British monarchy and how it operates," he stated.

He singled out Prince William and Prince Harry's conflict as the heir and spare the most profound among the identical conflicts in each royal family's recent generation.

The synopsis indicated how Lacey investigated the truth behind the two brothers' relationship.

The memoir set to be released is one of a series of upcoming publications regarding Prince Harry's personal relationships.

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