Prince Harry and Prince William differences surfaced much earlier before Meghan Markle, says author.
Tina Brown in her book about the royal family, claims that Harry always felt jealous of William and even 'vented' about it with ex-girlfriend Cressida Bones 10 years ago.
She writes in her book: "When he wasn’t venting about William, he was pouring out resentments about Charles."
"Friction between the brothers escalated over their professional alignments," Mrs Brown adds.
"William knew he had to be respectful of hierarchy when it came to his father’s ownership of the environmental platform, but he was less willing to accede to his brother."
Brown goes on to reveal Harry's dismay when William was made the patron of the charity Tusk Trust in 2015.
She quotes a friend of the siblings as saying: "Harry was a very, very angry man.
"I think those were absolutely Olympic rows."
Speaking to the Telegraph earlier, Ms Brown noted that Harry has been now "completely and utterly taken over by Meghan and his whole personality has changed".
"I do question how it will end," she added.
"[Maybe] he'll wake up and realise he's living in Goop and he has to get the hell out, go down the pub and see his friends."
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