The blond boy hammed it up for photographers before the ceremony, flashing the camera with silly faces and peace signs while outside St. Mark’s Church in Englefield.
Of course, Kate and husband Prince William had two very special members of the wedding party: son Prince George, 3, and daughter Princess Charlotte, 2 — who served as a page boy and a bridesmaid as well. (Having young bridesmaids is very common in British aristocratic weddings.)
The adorable royal siblings were “very” well-behaved at the ceremony according to wedding guests — a relief for Kate, surely, who told a garden party guest at Buckingham Palace on Tuesday that she was nervous about how her kids would act at the event,
“She said that they were all really looking forward to her sister’s wedding at the weekend, but she was a bit worried about how her children might behave,” garden party attendee Andrew Bates told reporters after his chat with the royal.
Charlotte wore an ivory silk dress with a frilled collar, a light pink sash and matching trim across the sleeves and neckline with hand-embroidered detailing. The bodice featured a vintage style lace panel and the dress carried a net petticoat with lace trim underneath. She also wore ivory opaque tights and beige soft leather shoes.
George wore an ivory double-breasted silk pleated shirt with Peter Pan collar and coordinating trim detail paired with knickerbockers in pale olive Vienne silk and a matching cummerbund.
Middleton, 33, and Matthews, 41, became engaged in July 2016.
The longtime couple has a “deep desire” to disappear from the spotlight in the longer term, a source told WHO.
Another source said they are looking forward to settling down and “having children and leading a quiet life.”
This story originally appeared on PEOPLE.com.