In PEOPLE’s exclusive photos, five-year-old George can be seen marching around with a smile on his face, while Charlotte can be seen holding on tight to mum Kate.
'George is a real star, quite the little chap,' a source told PEOPLE. 'He was having a great time, running around like the leader of the pack.'
Charlotte — who counts Sophie as one of her godparents — was one of three bridesmaids, while George was among the chosen four pageboys.
The pair were dressed in traditional attire.