In PEOPLE’s exclusive photos, George, 5, can be seen marching around with a smile on his face, while his sister Charlotte, 3, gives her big brother an amused look.
“George is a real star, quite the little chap,” a source told PEOPLE on Saturday. “He was having a great time, running around like the leader of the pack.”
Enjoying the sweet display, Kate, 36, flashed a warm smile while watching her son run about with his fellow page boys.
George and Charlotte were also on their cutest behavior when it came time to take wedding photos with the bride and her new husband, Robert Snuggs.
In the images, Kate holds Charlotte in her arms while looking on with a smile at her eldest son, who’s standing front and center near the happy couple.
For the weekend affair, both children wore traditional bridal attendant outfits in white and blue. Charlotte — who counts Sophie as one of her godparents — was one of three bridesmaids, while George was among the chosen four pageboys.
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The country wedding was also attended by Prince William, 36, who arrived with friends.
William was dressed in a traditional tailcoat while Kate wore a striking blue coatdress by Catherine Walker & Co.
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Charlotte and George were outfitted by one of Kate’s favorite children’s wear designers, Amaia. Charlotte wore a linen dress in ivory with royal blue embroidered edging from the upmarket label, which is based in a small boutique in London’s quaint Chelsea Green district. Meanwhile, George wore matching cropped blue trousers, with an off-white linen shirt accessorized with a blue cummerbund, also from Amaia.
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While attending the nuptials, the youngsters pulled off a royal wedding hat-trick in the process, as they both previously had roles in Prince Harry and Meghan Markle’s wedding in May and Pippa Middleton and James Matthews’ wedding in 2017.
True to form, the royal children had picture-perfect moments at the two earlier ceremonies as well. Fans loved when Charlotte stuck her tongue out in the car and showed her royal wave on the steps of St. George’s Chapel at Harry and Meghan’s wedding — and all eyes were on the youngsters at aunt Pippa’s wedding in May 2017, where they wore outfits by Pepa and Co.