The Royal Family are out in full force today to kick off celebrations for The Queen's Platinum Jubilee - marking 70 years of Queen Elizabeth II on the throne.
The four-day extravaganza begins with the Trooping The Colour parade and as part of this, The Duchess of Cambridge, The Duchess of Cornwall and George, Charlotte and Louis rode in a carriage down the Mall.
All five of them were dressed very sharply, but reagle-eyed viewers were particularly intrigued by the outfit the youngest royal was wearing.
For his first official appearance, Prince Louis, 4, had donned a sailor outfit - and it has a sweet link to his dad.
Louis' sailor outfit was previously worn by Prince William at the same event, Trooping The Colour, back in 1985.
The Duke of Cambridge, just three years old at the time, was snapped wearing the nautical look on the balcony at Buckingham Palace.
Prince George also previously wore one of his father's outfits to Trooping The Colour in 2015.
Royal fans loved the recycled outfit, with one person taking to Twitter to say: "How adorable."
Another wrote: "Prince Louis in a gorgeous sailor outfit. So cute!"
The Royal Family have a tradition of dressing children in sailor suits and nautical outfits which is said to date back to the time of Queen Victoria.
Princess Diana was a big fan of the sailor dress in the 80s and Kate Middleton has also been known to adopt that style at royal engagements.
Edward VIII and George VI have also notably posed in sailor suits as children.
The look is thought to be popular as it is timeless.
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