The Cambridge children made their debut in the Trooping the Colour carriage procession today. 
It was the first event of the four-day Platinum Jubilee celebration marking the Queen’s Queen’s 70-year reign. Below, Her Majesty, on June 5, 1952, her first Trooping the Colour as Sovereign. 
As the carriages left Buckingham Palace today, Princess Charlotte held her younger brother’s hand.
A wide shot of the carriages. 
More about the procession from this Hello! story.
Cheers went up from thousands of spectators on The Mall as they caught sight of the royal kids with proud parent Kate and the Duchess of Cornwall.
George, Charlotte and Louis smiled and waved enthusiastically as they sat in a row, with Louis, the youngest, in the middle of his older siblings.
And from The Daily Mail’s coverage.
The Duke and Duchess of Cambridge’s three children took centre stage today in the first royal carriage down the Mall at the start of Trooping the Colour – as four days of Platinum Jubilee celebration kicked off in style.
The children rode in a carriage with their mother and the Duchess of Cornwall.
Embed from Getty Images
The annual event honors the Queen’s birthday, and this year it has added significance, launching four days of celebrations marking the Queen’s Platinum Jubilee.
Another view of the young royals. 
This video shows a cute moment between Princess Charlotte and her younger brother.
WATCH: “Stop waving Louis!”
Beginners enthusiasm swiftly managed by his older sister, Princess Charlotte.#TroopingTheColour #HM70 #platinumjubilee pic.twitter.com/sQBvB7sEHF— Chris Ship (@chrisshipitv) June 2, 2022
As they arrived at Horse Guards Parade, where the military maneuvers take place, the national anthem was played, and the children bowed their heads. 
A quick video.
Crowds erupted in applause as Prince George, Princess Charlotte, Prince Louis and other members of the British royal family rode down the Mall in carriages and on horseback.
Watch Queen Elizabeth II’s #PlatinumJubilee celebrations live. https://t.co/cXViIsjfM6 pic.twitter.com/tBSsrCo2ZG
— The New York Times (@nytimes) June 2, 2022
More about today’s events from this People story.
This marks the first Trooping the Colour for the Duke and Duchess of Cambridge since 2019, as the event was massively scaled down in the past two years amid the COVID-19 pandemic. Queen Elizabeth, 96, attended solo in 2020 and was accompanied by her cousin Prince Edward, Duke of Kent in 2021, following the death of her husband, Prince Philip.
Horse Guards Parade. 
As Harper’s Bazaar explains, “Trooping the Colour, also known as The Queen’s Birthday Parade, is a military ceremony performed by regiments of the British Army that has taken place since the mid-17th century.” 
We return to the People article.
Although the Queen’s 96th birthday was on April 21, Trooping the Colour always takes place in the early summer of the second weekend in June. The reason is a practical matter more than anything: the weather is nicer! The tradition is believed to have started during the reign of King George II in 1748. George II was born in October, but the annual Trooping of the Colour became a celebration of the monarch as well as the armed forces.
After the ‘trooping of the colours,’ everyone returned to Buckingham Palace for the flypast. 
Prince George and Princess Charlotte. 
There were huge crowds for the event. 
A quick video of the scene on the ground.
Live scenes on The Mall #PlatinumJubilee pic.twitter.com/IgYzqc9NDo
— Chris Ship (@chrisshipitv) June 2, 2022
Here you see Typhoon jets forming the number 70. 
Another view of the precision flying team over London. 
Prince Louis points something out. 
In this image, you can see the crowds near Buckingham Palace. 
Prince Louis and his great-grandmother seemed to get along famously. 
The Prince was quite a character during parts of the flypast. 
Prince Louis and Princess Charlotte react to the noise.
Another funny face from Prince Louis. 
He was so animated he made many of the front pages. 
The renowned Red Arrows wrapped up the aerial display. 
Now for our look at what the children wore for the big day. Princess Charlotte was in the Blue Chiffon Dress ($77.50) by Patachou, a label based in Portugal. 
Made of polyester chiffon in cornflower blue, the dress has an angled bow at the collar, puffed sleeves, ruffled hem, and back zipper. The garment is lined in 100% cotton, and it can be machine washed. Patachou describes itself as “an accessible luxury brand that offers clothes and accessories for baby and children” Thank you to Found by Bojana for another terrific ID.
The Princess had French braids and a coordinating blue ribbon in her hair. In this photo, you can see the plaits.
Prince Louis was in a sailor suit that is very similar, if not identical, to one worn by his father wore to Trooping the Colour decades ago.
Below, a view from today and another from 1985.
Prince Louis, 4, Wears Dad Prince William’s Mini Sailor Suit for Trooping the Colour (37 Years Later!) https://t.co/efk4TQeS0H
— People (@people) June 2, 2022
I am hoping to find more photos to compare; I am not 100% convinced it is identical. The color looks different (although that could be lighting) and the tie length looks a little different. This could also just be me being bug-eyed from looking at hundreds of photos.
Unfortunately, I do not have any information on what Prince George wore.
A little wave goodbye from Prince Louis.
Embed from Getty Images
The second pic?
https://www.instagram.com/p/Ced8NsxO1VN/?igshid=YmMyMTA2M2Y=
Susan, I wonder if there is perhaps a typo above one of the photos of the Queen. It is shortly after pictures of the flypast. The caption says, “Prince George and his great-grandmother seemed to get along famously,” but the photo appears to be of HM and Louis.
Thank you for the wonderful work you do here and on WKW.
Thank you for the heads-up, Anne! I think I may have Jubilee Brain! 🙂
As you say, Susan, it is really difficult to be sure if it is the same outfit. From one of the carriage phots it is clear that the whole top is subtly striped. The photos of William on the balcony are not as clear.
However, on balance, I would say it is the same: Catherine was had her children re-wear other items from William’s childhood wardrobe previously and I really do not see her spending money on a little sailor suit for one wear!
I think Luis is older than William was when he wore the sailor suit. William looks younger than 4. For that reason I am thinking it is not the same but a very nice nod to the past.
I also think it is possible that this is the same outfit. William was 3 years old in 1985. Louis is 4.
Thinking about Lotti’s shoes. Mabe a white version of Prince Philip Memorial shoes? Or a white mary-jane.
She’s a young lady now ♥