Betrayed: Prince William Still 'Feels Let Down' By Prince Harry After Platinum Jubilee: Source

Prince William's hurt feeling may be partially responsible for why he didn't seem to mingle with his brother and his family at the Platinum Jubilee.

Although Prince Harry and Meghan Markle made the trek back to the U.K. to celebrate Queen Elizabeth II's 70 years on the throne, sources claimed William and Kate Middleton didn't say a word to the Duke and Duchess of Sussex, or even make an effort introduce their children to Lilibet.

Last Friday, both royal brothers attended the Service of Thanksgiving at St. Paul's Cathedral, but they were seated on opposite sides of the church. A friend of the royals speculated the Duke of Cambridge hasn't gotten over how much his younger brother hurt him when he abandoned his royal duties and started a new life in the United States.

"He's still deeply upset about it and feels let down, but he’s moved on," the friend told The Sunday Times, adding William was "incredibly worried about having all the family there, and what everyone was going to say."

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Although tensions ran high, the friend noted William was "so relieved" the media mostly focused on the Queen, Prince Charles and the royal children's antics. "He was really pleased about that."

According to royal author Christopher Anderson, William isn't the only member of the family disappointed in Harry and Meghan's decision. Anderson admitted the Queen's refusal to be photographed with Lilibet, 1, hit the couple particularly hard.

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"We now know that the Queen, well, the men in grey who really handle things, would not permit the Queen's photograph to be taken with Lilibet," he told Royally US per The Sun. "That spoke volumes, it was a really bitter pill for Meghan and Harry to swallow."

"You have to remember, Archie was photographed with the Queen, and Prince Philip, and Doria Ragland when he was two days old," he added. "It's a tradition to be photographed with the monarch when you're a grandchild or a great-grandchild. But this was a really different feeling."