The Queen is normally joined by the royal family to celebrate her official birthday, Trooping the Colour, on the second Saturday of June every year.
However, due to the pandemic, the ceremony had to be drastically pared down in the last couple of years. This year, though, as the monarch prepares to celebrate her Platinum Jubilee, Thursday's event should be one to remember.
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The Queen will of course be joined by other senior royals on the Buckingham Palace balcony. Last time that happened, back in 2019, the Duke and Duchess of Cambridge made their debut as a family-of-five on the Buckingham Palace balcony.
Let's take a look back at William and Kate's sweetest moments during their loved-up appearance...
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Making a joint debut, the Cambridges were the definition of a perfect family, smiling and laughing as they watched the spectacular RAF flypast from the balcony of Buckingham Palace.
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Royal watchers noted just how happy William and Kate, who have been married for 11 years, looked, and how complete they were with their little ones in tow.
It was a rare opportunity for fans to see all five Cambridges out and about, as the children make rare public appearances. Louis was in fact attending his very first Trooping the Colour at 14 months old.
The Cambridges had previously made an appearance as a family-of-five in May 2019 to attend the Chelsea Flower Show, where Kate had helped co-design the RHS Back to Nature garden.
But before that, the family hadn't been seen in public together since Louis' christening in June 2018.
Kate bounced her baby boy in her arms, but it wasn't long before Louis wanted to be carried by daddy.
The parents-of-three showed Louis his first flypast, pointing up to the sky as the planes and helicopters whizzed by.
Kate stroked her son's hair while he sucked his thumb.
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The then 14-month-old kept his parents entertained on the palace balcony.
The Duchess bent down to chat to her elder children, Prince George, then five, and Princess Charlotte, then four, during the flypast.
Kate looked after George and Charlotte while William had his hands full with Louis.
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