The wind seemed to take its toll as Charlotte, George, and the other bridesmaids and page boys walked up the steps into the church, with one of the page boys even tripping up.
They all wore green floral detailing around their waists - a bow for the girls and cummerbunds for the boys, while Charlotte and the bridesmaids also had flowers in her hair.
Charlotte walked up the stairs along side her brother, then turned around to give the crowds a final wave before she walked inside.
As George and Charlotte arrived at the church, they were seen eagerly waving to the crowds through the window of the car.
We 💖 Princess Charlotte's royal wave! 👋 pic.twitter.com/tzHXgZQ0Cq— This Morning (@thismorning) October 12, 2018
George and Charlotte are among Princess Eugenie’s page boy and bridesmaids, along with Robbie Williams’ daughter Theodora. Other bridesmaids include Savannah and Isla Philips, Mia Tindall and Maud Windsor. Louis de Givenchy will also be a page boy alongside George.
Prince Louis, who has only been seen in public twice at his birth and his christening, has not yet been seen at the wedding.
The wedding is taking place at St George’s Chapel in Windsor, where the Duke and Duchess of Sussex wed in May. The couple will be hitched by Dean of Windsor David Conner, who also conducted Meghan and Harry’s wedding.
Princess Beatrice, Eugenie’s older sister, is maid of honour, while the groom’s brother, Thomas Brooksbank, is the best man.
The Queen is hosting an afternoon reception in St George’s Hall, within the castle, followed by an all-nighter at the Royal Lodge in Windsor Great Park.