Prince Harry has "poison in his blood and wants to show his power over older brother Prince William, a royal expert has said.
There has been much made of the rift between the two brothers with their frosty relationship reportedly sparked by William's concerns over Harry's fast-developing relationship with Meghan Markle ahead of their royal wedding in 2018.
The tense row quickly boiled over - with Harry claiming his brother was "trapped" within the royal system during a bombshell interview with Oprah Winfrey after quitting as a senior royal.
Later this year, Harry is releasing a tell-all memoir, which he promises to be an "accurate and wholly truthful" account of his life so far.
And according to Angela Levin, who has written a biography of Harry, he could be ready to speak out more about his family.
She told the Daily Mail's Palace Confidential show: "He’s now so bitter and resentful that he will say what he really feels and see things that he accepted years ago as now being absolutely dreadful.
"I think he really wants to show his power over William because he was fed up with being the spare rather than the heir – I think he’s got a lot of poison running in his blood now about what he feels about his background and his family.
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"And I think he doesn't mind if he hurts people because he feels that he has been hurt by them."
Angela's comments come after insiders have claimed that Harry's memoir will be "juicy" and should make the Royal Family "nervous".
Almost a year ago, Harry unleashed a "tsunami of fear" in royal circles by revealing he was to release a tell-all book.
Harry has been working on the “intimate and heartfelt memoir" with the help of ghostwriter JR Moehringer – a Pulitzer Prize-winning author - and he promises it will be "accurate and wholly truthful".
And according to insiders, Harry is set to drop more "explosive truth bombs" in the book - although a release date for the memoir has not yet been revealed.
One insider that works in publishing told Page Six : "It’s juicy, that’s for sure.”
While another publishing insider also told them: “There’s a lot of new stories in there about the past that Harry has not spoken about before, about his childhood … there is some content in there that should make his family nervous.”
Meanwhile, a book about Meghan that has been described as one she "will be dreading" has been given a release date.
Well-known biographer Tom Bower has penned the book, which is called Revenge Meghan, Harry and the war between the Windsors.
It will be published next Thursday (July 21) by Blink Publishing after the writer spent 12 months gathering information and speaking to both friends and enemies of Meghan - although has not worked with the duchess herself.
Mr Bower, who has been described as "pulling no punches" previously said that it will "tell the truth" upon its release next week.
