Prince Harry hoped to win back Britons with his attendance at Queen Platinum Jubilee with wife Meghan Markle.
Speaking exclusively to Daily Star, Deborah Davies, the former Real Housewives of Cheshire star said: "They had to let him [Prince Harry] come to the Jubilee or they would look bad 'in the book'.
"From Harry's perspective, he thought they'd [Harry and Meghan] have far more of the limelight and suddenly be in favour with the British public.
"It didn't work out that way, I see Harry as being angry that they weren't given a more public position in the celebrations."
Deborah continued: "In his eyes, it was their time to shine.
"Without cooperation over the contents of the book though they were firmly put in their place by William – it's him calling the shots, not Charles!"
Earlier, Deborah conjectured William might have asked to read Harry's memoir before the release.
She said: "I think there's a legal wrangle taking place regarding Hapless Harry's book that's due out later this year.
"I think that William has asked to see the content and has been refused and that's why William didn't go to Frogmore to celebrate Lilibet's birthday.
"I see William as being incandescent with rage towards Harry."
"Mental fitness for me is just really learn to shut down," Williams, 40, said
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