The Duke could be seen two rows back from the Prince of Wales in the Abbey shooting a seething look at his brother.
William sat next to his two children and his wife Kate in the front row, which was reserved for working royals only.
Meanwhile, Harry was relegated to row three and was sitting without his wife Meghan Markle, who remained stateside for the big occasion.
It comes after the bitter fallout between Harry and the Royal Family following the Duke’s move across the pond.
He sat alongside Princess Eugenie’s husband, Jack Brooksbank, and the late Queen Elizabeth II’s cousin Princess Alexandra.
The Sussexes stepped back from their royal duties and have since unleashed a series of bombshell claims, including in a televised interview with Oprah Winfrey in 2021 and lately in Harry’s tell-all memoir Spare.
Harry spilled intimate details about his family and his relationship with them in the damning book. In one passage, the Duke of Sussex even claims his brother once took a swing at him.
The Duke also left Buckingham Palace in the dark for weeks over whether he would even make it into the Abbey today.
The Prince was also eager to head back to the US to see his immediate family following the ceremony.
In fact, the 38-year-old Duke reportedly rushed back to California to make it home in time for Prince Archie’s birthday celebrations.
Archie’s fourth birthday coincided with King Charles’s historic occasion, which some claim is why Meghan never made the trip across the Atlantic.
Meghan is allegedly throwing a “low-key” party with close friends and relatives.
According to royal biographer Omid Scobie, the Duchess of Sussex missed the crowning of King Charles to “protect her peace”.
He claimed that “[they] would rather the attention didn’t go onto her”, adding that “if you look back at some of Harry and Meghan’s biggest problems, it was all down to the fact that the attention was always on them at times when it shouldn’t have been.”
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