Princess Charlotte tantrum: Royal falls from balcony at Trooping the Colour 2018

Prince George made a hilarious mistake at the Trooping the Colour — and the internet loves it

In a lighter moment, a young fox was spotted on the parade ground before the spectacle began, running out from under the stands as it tried to find a way into nearby St James's Park.

As with previous years, the Duchess of Cambridge and the Duchess of Cornwall are expected to take part in the Queen's carriage procession.

The Duke and Duchess of Cambridge arrive in a vintage Rolls Royce Phantom together this morning.

Trooping the Colour is a ceremony deeply rooted in the history of the United Kingdom.

Meghan and Prince Harry looked relaxed as they made their way along the Mall while crowds strained to catch a glimpse of the couple post-Royal wedding.

Prince George and Princess Charlotte couldn't have looked cuter in their smart little outfits - co-ordinating perfectly with mum Kate, who wore a gorgeous pale blue Alexander McQueen dress. She is due to join Queen Elizabeth in Cheshire for her first solo appearance alongside the Queen on Thursday.

The royal colonels, all on horseback, will accompany the Queen, Prince Charles, Princess Anne and Prince William.

Also riding in the ceremony for the first time was the Duke of York in his new role as Colonel of the Grenadier Guards.

Among the guests was Defence Secretary Gavin Williamson, the Prime Minister Theresa May normally attends but is at a G7 meeting of world leaders in Canada.

For those unfamiliar, the Trooping of the Colour is the most highly-anticipated event in the royal calendar (well, aside from last month's Royal Wedding, of course) and is steeped in English tradition. Flags, or colours, were "trooped" so soldiers in the ranks would be able to recognize them.

The Trooping the Colour is a ceremony performed by regiments of the British and Commonwealth armies to mark the official birthday of the British sovereign. Although Queen Elizabeth already turned 92 on April 21, the royals understandably prefer to party and socialize in warmer weather.