PHOTO: JOHN THYS/AFP/Getty Images

When it comes to setting trends while still keeping in mind classic royal traditions, Kate Middleton walks the line without crossing it. Her style is classic yet still very modern—hello, she loves the cold-shoulder look as much as we do. The duchess also loves to mix up her beauty look—ICYMI, she apparently changes her hair for each pregnancy—but we dare you to name a time you’ve seen Kate wearing red nail polish or coral on her fingers. Coming up blank? It turns out there’s a very specific reason why.

Marie Claire UK reported recently that only natural-looking nails are permitted at official royal events—which tend to be where and when photos of her get taken. That kind of explains why Queen Elizabeth II has been wearing the same shade of polish, Essie’s Ballet Slippers, since 1989. According to Essie, it’s “the only color Her Majesty would wear.” It is a cult classic, after all. And hey, if you know what you like…

Kate wore a similar, sheer pink shade on her wedding day. Her manicurist Marina Sandoval told the Daily Mail in 2011 that she mixed Bourjois Rose Lounge and Essie Allure to create the custom shade.

Prince Harry’s girlfriend and mostly-likely-soon-to-be-official fiancé, Meghan Markle, has also been spotted wearing natural nail shades when she’s out with Harry: at the Invictus Games, she had her nails painted with a sheer pinkish-white shade.

So why the no-bold-nail-polish rule in 2017? We love those shades, personally. But royals are expected to dress and behave according to strict, traditional codes—they can’t sign autographs, for example. And if it that’s the royal rule, we’ll respect it. The diamonds in Princess Diana’s tiara that Kate’s been known to wear make quite the statement anyway.

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