"Having all of them there was very important to him ... he was absolutely insistent that his wife's family be properly included," Hardman penned in Charles III.
OK! previously reported William seeing his father's transition into being king inspired him to envision his eventual enthroning, but Prince Harry will most likely not be included due to his controversial book, Spare.
"I hear that William has no intention whatsoever of apologizing and remains incandescent, especially around the way his wife, the Princess of Wales, has been treated," the confidant spilled to a publication. "The relationship isn't even rock bottom now, it's non-existent. And I just don't see, if Harry were to come to the Coronation, how William could even bring himself to look his brother in the face."
While the Duke of Sussex and the Prince of Wales aren't expected to reconcile in the future, William will eventually ascend to the throne alongside the Princess of Wales. When Kate first joined the royal fold she was in her 20s and struggled with public speaking and appearances, but she has since blossomed into a powerful global figure.
Kate's royal evolution was a focal point in William & Kate: Too Good To Be, exploring how the princess elevated her wardrobe to align with William's lifestyle.
"We hadn't expected Kate and her family to turn up, and myself and a number of photographers and journalists were all standing on a press stand together," Rebecca English said when discussing Kate going to William's 2006 passing-out parade.
"Suddenly, out of the corner of her eye, we saw Kate and her mother and father being ushered down to the front of the seating," English stated. "I remember turning to the person next to me and saying, 'That's it, it's a done deal. This woman is going to be our future queen.'"
"Suddenly, the engagement whispers were starting," she continued. "There was intense pressure on William and Kate, and, short of printing the tea towels, everyone had these two walking down the aisle imminently."
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"The low-slung jeans, denim skirts, and spaghetti straps of her early 20s were swapped out for smart blazers, quality suits, and refined gowns, with a more polished, palace-ready look emerging," she explained.