While Princess Charlotte took control during Prince Harry and Meghan Markle‘s wedding, her parents Prince William and Kate Middleton were happy to stay behind the scenes, but they let loose during the private evening reception.
“William was in a jokey, wonderful mood at the party,” a royal wedding guest tells PEOPLE of Harry’s best man and older brother. “He must have been relieved that it wasn’t all about him.”
All eyes were on Charlotte, 3, and Prince George, 4, though. The young royals served as a bridesmaid and a page boy, respectively, just like they did for their aunt Pippa Middleton’s wedding last spring. George’s role even allowed him to wear pants in public for the first time, an exception to the usual royal protocol that requires young royal boys to wear shorts until they’re 8 years old. On Saturday he mirrored his dad and uncle in a miniature version of the Blues and Royals coat that they wore to the wedding ceremony, and matched with a pair of custom-made black pants by Savile Row tailors Dege & Skinner, that featured a red stripe down the side.
Kate, 36, liked seeing her two kids in the spotlight, though newborn Prince Louis stayed home on Saturday.
“She was [in] great form,” the wedding guest recalls. “She and William were saying how thrilled they were to have their children there taking part.”
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And of course, William, 35, felt elated to see his younger brother so happy as he tied the knot with Markle, 36. “He is so proud of his brother,” the attendee says.
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The whole royal family came together to appear in Harry and Markle’s official royal wedding portraits that were released by the palace on Monday.