The departure of Prince Harry and Meghan Markle from the monarchy reportedly caused an intense relationship fallout between the Duke of Sussex and Prince William. However, way before that, the relationship between the brothers has already been strained.

And as has been reported in the past, one royal expert claimed that the "Suits" alum played a big role with the said rift among the brothers. 

In the book "Battle of Brothers: William and Harry - The Inside Story of a Family in Tumult," royal historian Robert Lacey delved into the drama that triggered the rift between the two royals. 

In his book, he mentioned that things started to go downhill when the former Hollywood actress came into the picture. 

After marrying the then 33-year-old Prince Harry in May 2018 at the famous St George's Chapel at Windsor Castle, Meghan Markle officially became a member of the royal family. 

Therefore, he has a set of rules and royal protocols to follow.

Unfortunately, the Sussexes are known to veer away from the royal traditions, which upset the Duke of Cambridge. 

Lacey shared in his book that Prince William reached his limit when the couple welcomed their son, Archie Harrison. 

He explained that the Sussexes chose to welcome their firstborn child in Portland Hospital, a private American-owned facility in London, instead of the traditional Lindo Wing at St. Mary's Hospital in Paddington, where the young Cambridges were born. 

Aside from Prince William and Kate Middleton's kids, it was also the place where the late Princess Diana gave birth to her two sons. 

Another thing that upset the future king of England was how the Sussexes wanted to keep things in private, including baby Archie's christening, which is considered as a royal tradition. They even kept the identities of his godparents hiddent. 

Prince William reportedly had enough with the Sussexes' behavior and their reputation to go against royal protocol. 

For him, it was all "too much," which prompted the distant relationship between the two. 

"I've put my arm round his shoulder all our lives together,' said the prince to a friend, explaining why Harry and Meghan's behaviour and the succession of erratic decisions surrounding Archie's birth and christening-particularly the weird concealing of the godparents-had led to the rupture between the brothers that Harry would describe later as the pursuit of 'different paths.'

"I can't do it any more," said William. 

At the time, multiple reports cited that it was the only royal christening with no access to the public.

Moreover, in their defunct Sussex Royal Instagram account, the couple shared an official photo featuring the members of the royal family with Meghan Markle's mom, Doria Ragland. The photo includes Prince Harry and Kate Middleton, baby Archie's grandparents, Prince Charles and Duchess Camilla, as well as Princess Diana's sisters, Lady Sarah McCorquodale and Lady Jane Fellowes. 

Royal Threat? 

Following the intense feud between Prince Harry and Prince William, Lacey also noted that the rift could be seen as a "danger" for the Crown. 

In his interview with Express UK, the royal expert explained that if the two failed to reconcile and forget the past, the public might suspect the "genuineness and behaviour of members of the Royal Family."

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Tags: Prince Harry Prince William Meghan Markle royal family