Princess Charlotte is already a mini fashion icon.
Prince William and the Duchess of Cambridge's middle child has fan websites dedicated to her style, the yellow cardigan she wore in a photo released for her second birthday became the most searched-for royal outfit that entire year, and the Little Alice London dress she wore to meet Prince Louis at St Mary's Hospital in April sold out in 24 hours.
Just last week, iconic fashion magazine Vogue pondered if Charlotte is "the brightest star of the British Royal Family," noting that while her adorable waves and curtsies to the public have stolen all our hearts, the "Charlotte effect" means all the clothing she wears instantly sells out.
Not bad for a three year old.
But whether you're a Charlotte fashion follower or just a casual fan, you've likely noticed that the princess is never photographed wearing pants.
Even when she's frolicking and romping barefoot in fields with her shorts-clad older brother, Prince George, just like she did in June while attending Prince William's charity polo match (and by the way, the Amelia floral dress she wore there is also sold out).
And it turns out there's a very specific reason Charlotte only wears dresses: so she'll never look dated in photographs.
"If they wear very simple things ... it's timeless in that you can't really date a specific photo or put them in something that seems out of date," kidswear designer Rachel Riley, who has dressed Prince George, 5, told The Telegraph last year.
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The Duchess of Cambridge favours traditional styles for her kids, The Telegraph noted.
"They have chosen a very traditional look and are a traditional family," Riley said.
And that's something the new Duchess of Sussex, Meghan Markle, has had to take into account with her own fashion choices. According to the Daily Mail, Markle wanted to wear a Stella McCartney tuxedo suit to an evening event on their upcoming tour of Australia, but Prince Harry gave it the thumbs down.
"Meghan is being told she needs to stop dressing like a Hollywood star and start dressing like a royal. Meghan wanted to wear a tuxedo-style suit but Harry said it wasn't traditional enough," a source from one of the fashion teams that visited Kensington Palace in recent weeks told the Daily Mail.
Princess Charlotte's traditional smock dresses aren't the only signature style among the royal children. Prince George, as most royal-watchers know, is basically never not wearing shorts.
And there's a very specific reason for this, too: it's adorable.
JK, it's actually because it's a tradition among the upper class, aristocracy, and the royals, according to Harper's Bazaar.
"It's a very English thing to dress a young boy in shorts," etiquette expert William Hanson told the magazine. "Trousers are for older boys and men, whereas shorts on young boys is one of those silent class markers that we have in England. Although times are (slowly) changing, a pair of trousers on a young boy is considered quite middle class – quite suburban. And no self-respecting aristo or royal would want to be considered suburban. Even the Duchess of Cambridge."
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