Kate, Duchess of Cambridge, beamed as her five-year-old son, dressed in a collarless white shirt, sky-blue knickerbockers, white stockings and white loafers, showed off his marching skills, leaving guests in hysterics.
George giggled as he was snapped leading other children in the bridal party in a march outside St Andrew’s Church in Letheringsett, Norfolk.
But George’s sister, Princess Charlotte, didn’t share her brother’s enthusiasm for her special role as flower girl and instead looked shy and timid as she clutched her posies.
The young royals took their leading roles at the English country wedding of bride Sophie Carter, their mum Kate’s close friend, to Robert Suggs.
Keen to coordinate with her two children, Kate, 36, wore a matching periwinkle blue coat dress by Catherine Walker, teamed with a floral headpiece by Jane Taylor.
Charlotte, dressed in a white smock dress with a ruffled collar and blue edges, was not in her usual confident mood and looked unimpressed as she kept close to her mother.
And at one point the duchess lovingly held her three-year-old daughter in her arms, while George flashed a cheeky grin at the camera.
The prince and princess were also joined by their father, Prince William, who wore a traditional morning suit.
But there was no sign of their baby brother, Prince Louis.
One onlooker told The Sun: “George was having a great time, running around like the leader of the pack.
“He was loving his responsibility and played up to the crowd. At one point everyone chuckled as he began marching about.
“Charlotte wasn’t enjoying being the centre of attention quite so much.”
Brother and sister George and Charlotte took their starring roles among three other bridesmaids and four page boys taking part in the ceremony.
They all wore outfits from Amaia Kids.
Duchess Kate and Sophie were schoolgirls together at Marlborough College and Sophie is also one of Charlotte’s godmothers.
Kate’s parents, Carole and Michael Middleton and brother, James, were also guests at the wedding in Norfolk.
While Kate’s sister, Pippa, who is pregnant with her first child, was absent from the special day.
Prince George and Princess Charlotte are no strangers to taking on leading roles at weddings – they took on pageboy and flower-girl duties at their aunty Pippa Middleton’s wedding to James Matthews back in May 2017 and uncle Prince Harry’s Royal Wedding to Meghan Markle in May this year.