Did Prince William call upon his grandmother Queen Elizabeth II for help smoothing things over between his father Prince Charles and his mother-in-law Carole Middleton?

Did Prince William call upon his grandmother Queen Elizabeth II for help smoothing things over between his father Prince Charles and his parents-in-law, Michael and Carole Middleton?

That’s what Tom Bower says in his new unauthorized biography of the Prince of Wales, Rebel Prince: The Power, Passion and Defiance of Prince Charles — pages of which were excerpted in The Daily Mail on Saturday.

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The British investigative journalist claims that Prince Charles’ felt “usurped” by the Middletons and “isolated” from grandchildren Prince George, 4, and Princess Charlotte, 2, with William and wife Kate Middleton choosing to spend Christmas with her parents rather than with the other royals and setting up their home base miles away from Highgrove (Charles’ residence) to Norfolk “where they could preserve their privacy.”

Image zoom Prince William and Prince Charles John Stillwell - WPA Pool/Getty images

Bower claims that several of the Queen’s courtiers allegedly “decided to ignore Carole Middleton on social occasions” after picking up on Charles’ alleged fears of being overshadowed.

William became “infuriated” and “consulted with his grandmother,” Bower claims. The Queen countered “the hurtful snubs against Carole” with an invitation to drive her around the Balmoral estate — and allegedly inviting a TV cameraman to film their outing, according to Bower.

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Meanwhile, Charles attempted to bond with Kate by inviting her to her first opera in the Royal Box at Covent Garden. The night out was a bust — Charles’ hope to convert Kate to classical music lost because the production of Bellini’s La Sonnambula (The Sleepwalker) was “awful,” Bower claims.

Such instances led Charles to worry that the media attention was switching to William and Kate. “Charles saw Kate and William as the new stars and feared he’d be in trouble,” Robert Higdon, the chief executive of Charles’ charity foundation in America, told Bower.

The prince was even disappointed his son and daughter-in-law were invited by the Canadian government to tour the country in September 2016 before he was, Bower claims.

Image zoom Camilla, Duchess of Cornwall, Prince Charles, Queen Elizabeth II, Prince Philip, Prince William and Kate Middleton MEGA

According to Bower, Charles’ connection to his sons William and Prince Harry had been strained during his divorce from Princess Diana, with Charles allegedly believing “Diana had poisoned the boys’ minds towards their father.”

After her death in 1997, “the brothers had to cope with a continuing onslaught of public revelations about their parents’ adulterous relationships,” Bower writes. Charles’ eventual marriage to his mistress, Camilla, Duchess of Cornwall, didn’t help — her presence “a constant reminder of their mother’s torment.”

The brothers would even enter Clarence House “through the servants’ quarters, in order to avoid both their father and Camilla,” Bower claims.

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While Charles may have worried about William and Kate “taking the limelight,” Camilla was “unconcerned.”

“She didn’t give a damn,” Higdon told Bower.