Whilst her husband Prince William donned his military regalia to ride in the parade, Catherine arrived via carriage with their three children, Prince George, eight, Princess Charlotte, seven, and Prince Louis, four.
She then joined the royal family on the Buckingham Palace balcony and looked every inch the queen-to-be as she waved to the crowds and attended to her three little ones.
Dressed in a navy suit with a blue tie, Prince George looked as dapper as ever as he looked out into the crowd.
Meanwhile his sister Princess Charlotte looked cute as a button in a blue chiffon dress with a bow and endearing plaits.
Rounding out the Cambridge family was the Duke and Duchess of Cambridge's youngest child, Prince Louis, who looked all grown up in a sailor suit as he shared some words with his great-grandmother.
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At their last appearance in 2019, George, Charlotte and Louis were not old enough to ride in the carriage procession with their mother, Catherine, Duchess of Cambridge, but were spotted smiling from the window.
They then joined their parents to watch the flypast for a brief but memorable moment.
This article originally appeared on our sister site, Now To Love.