Yui Mok/PA Wire
The two tied the knot at St. George's Chapel at Windsor Castle on Friday. While the attention was certainly centered on the bride and groom, Prince George and Princess Charlotte had a few show-stopping moments, too.
The 5-year-old prince served as page boy while his 3-year-old sister served as a bridesmaid. Luckily, they had a bit of practice before the big day. After all, they performed the same roles at Prince Harry and Meghan Markle's wedding in May and at Pippa Middleton and James Matthews' wedding the year before.
Their little brother Prince Louis, however, was not in attendance. The young royal was most likely too little to attend. He is, after all, only five months old.
To see photos of all the siblings' adorable moments, check out the gallery.