Prince Harry's ongoing feud with his big brother, Prince William, could worsen with the latter getting closer to their stepmom, Queen Camilla, according to a royal expert.

Tom Quinn, a royal biographer and author of "Kensington Palace: An Intimate Memoir from Queen Mary to Meghan Markle," weighed in on the royal siblings' relationship amid King Charles' and Kate Middleton's cancer battles. He claimed Prince William's closeness with their stepmom wouldn't help the brothers' relationship.

"He [Harry] really distrusts that William actually gets on rather well now with Camilla -- Harry will see this as a betrayal," Quinn told the Mirror. "He was shocked when William realized that Camilla, far from being the monster they thought her when they were children, is actually a rather nice woman."

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Queen Camilla, King Charles and Prince Harry
Camilla, Duchess of Cornwall, Prince Charles, Prince of Wales and Prince Harry attend the opening ceremony for the Invictus Games, presented by Jaguar Land Rover at Queen Elizabeth Olympic Park on September 10, 2014 in London, England.
(Photo : Paul Thomas/Getty Images for Jaguar Land Rover)

Quinn believes that there's something in Camilla that drew the Prince of Wales, especially since both of their spouses have similar health battles. However, the royal commentator said Prince Harry wouldn't be happy about Prince William being close to their stepmom. The Duke of Sussex was open about his disapproval of Camilla, the third party in King Charles and the late Princess Diana's marriage.

"She is exceptionally good at listening with a sympathetic ear, and William has definitely warmed to that. Harry, on the other hand, sees this as one more example of William letting the side down -- for Harry things have never moved on really since his mother died," Quinn added. 

King Charles, Queen Camilla and Prince Harry
 Prince Charles, Princess Camilla and Prince Harry watch poppies dropped from a Lancaster bombe as she stands next to Prince Andrew on the balcony of Buckingham Palace during the celebrations marking the end of World War II in London 10 July 2005.
(Photo : JAMES VELLACOTT/AFP via Getty Images)

"For Harry, Camilla was the wicked stepmother back then, and she still is. It's all very sad, but shows that the huge geographical divide between the brothers -- Harry in America, William in London -- has become a physical manifestation of their emotional separation."

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Prince Harry called Queen Camilla a "villain" and "dangerous" in his memoir "Spare," released in January 2023. In an interview for "60 Minutes," Andrew Cooper asked Meghan Marke's husband why he made the statement.

"She was the third person in their marriage. She needed to rehabilitate her image," Prince Harry said of his stepmom.

Prince Harry also claimed that Camilla "sacrificed me on her personal PR altar." He added that he and Prince William didn't initially agree with King Charles' marriage to Camilla but eventually conceded because they "wanted him to be happy and saw how happy he was with her."


King Charles, Prince William and Prince Harry
Prince Harry, Prince Charles, Prince of Wales and the Prince William, Duke of Cambridge pose for a photo with members of the Military Wives Choir at the Business in the Community (BITC) 2014 Responsible Business Awards Gala Dinner at the Royal Albert Hall on July 8, 2014 in London, England.
(Photo : Dominic Lipinski - WPA Pool/Getty Images)

Tags: Prince Harry Prince William Queen Camilla