Kate Middleton and Prince William at King Charles' coronation.Photo: Neil Mockford/Getty

LONDON, ENGLAND - MAY 06: (L-R) Sophie, Duchess of Edinburgh, Princess Charlotte of Wales, Catherine, Princess of Wales, Prince Louis of Wales, Prince William, Prince of Wales on Buckingham Palace balcony during the Coronation of King Charles III and Queen Camilla on May 06, 2023 in London, England. The Coronation of Charles III and his wife, Camilla, as King and Queen of the United Kingdom of Great Britain and Northern Ireland, and the other Commonwealth realms takes place at Westminster Abbey today. Charles acceded to the throne on 8 September 2022, upon the death of his mother, Elizabeth II. (Photo by Neil Mockford/Getty Images)

Kate MiddletonandPrince Williamare reflecting on a historic day.

The royal couple shared a heartfelt Instagram clip Saturday, just hours after appearing at Westminster Abbey in London for the crowning ceremony ofKing CharlesandQueen Camilla.

“What. A. Day,” William, 40, and Kate, 41, captioned the video. “Thank you to everyone who made it happen#Coronation.”

In the clip shared to the Prince and Princess of Wales' jointInstagram account, Prince William and Middleton could be seen wearing formal robes and mantels for the historic occasion. Their three kids —Prince George, 9,Princess Charlotte, 8, andPrince Louis, 5 — also joined their parents at the event.

The video, which featured flashes of other scenes from the coronation, ended with a view of King Charles and Queen Camilla waving to excited onlookers.

As previously reported,Prince Williamand Middleton wore the formal attire at the request of the King and Queen, and William specifically wore the ceremonial dress uniform of the Welsh Guards.

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Christopher Furlong/Getty

Vice Admiral Sir Timothy Laurence, Sophie, Duchess of Edinburgh, Princess Charlotte of Wales, Anne, Princess Royal, Catherine, Princess of Wales, Prince Louis of Wales, Prince William, Prince of Wales, Page of Honour Lord Oliver Cholmondeley and Prince George of Wales pose on the Buckingham Palace balcony during the Coronation of King Charles III and Queen Camilla

During thehistoric crowning ceremonyon Saturday, the Prince of Wales, who is heir to the British throne, assisted Baroness Merron and bishops in putting the Robe Royal on King Charles before he was crowned with the St. Edward’s Crown.

Prince Williamalso knelt before King Charles and placed his hands in his father’s afterward. He said, “I, William, Prince of Wales, pledge my loyalty to you and faith and truth I will bear unto you, as your liege man of life and limb. So help me God.”

Charles named William Prince of Wales followingQueen Elizabeth’s death in September, providing him with the traditional title for the heir. “Talking about the future of the country and their future roles has strengthened their bond,” a source who knows both King Charles andPrince Williampreviously told PEOPLE.

The source also told PEOPLE thatPrince HarryandMeghan Markle’s decision to move to California after stepping back as senior members of the royal family in 2020 “brought [William and Charles] closer.”

Harry, 38,attended his father coronation’s ceremony, despite not playing an official role in the service.

He and William did not appear to cross paths at the coronation, as they didnot sit together during the church service. Harry waspictured smiling from ear to earat the event, wearinga morning suitfor the occasion.

source: people.com