The world's biggest fashionista is a lot younger than you think, it turns out.

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According to a new report by eBay, Princess Charlotte is the queen of the copycats. In other words, when she wears something, it's almost instantly sold out. eBay said the 2-year-old has the "biggest spend power" of any of the royals, as there are more searches for her outfits than even those worn by her extremely fashionable mom, Duchess Kate.

Murray Lambell, eBay's vice president of trading, told The Daily Mail, "The Royal Family are hugely popular with British buyers with Her Majesty regularly attracting the attention of shoppers. But it's the youngest generation of royals who really generate the must-have fashion items -- and driving a new generation of shopping [behavior] on eBay."

For instance, after photos of Charlotte's second birthday -- during which she wore a yellow cardigan -- emerged, searches on eBay "increased tenfold" and the item "instantly" sold out, Daily Mail said.

"There were three searches an hour for the item itself, 'yellow cardigan,' across the whole month, peaking on the day the photo was first released," eBay's spokesperson said.

Similarly, when she wore a blue dress during a family tour of Germany, searches for "Princess Charlotte Dress" increased six-fold.

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To be fair, when Duchess Kate is seen in certain clothing, interest almost always increases too.

Still, it sounds like it's Charlotte's fashion world.