Kate Middleton's internal fashion mantra lately: "When it's right, it's right."

OK, we can't know that for sure, but if Middleton's wardrobe could speak for itself, it would be screaming "uniform" from the rooftops. The Duchess of Cambridge has been wearing outfits that err on the side of carbon copies, and that became abundantly clear during the Centenary of the Royal Air Force on Tuesday.

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The royal broke her maternity leave for the unexpected appearance on Tuesday, wearing tried-and-true favorite designer Alexander McQueen coupled with a matching fascinator. Her pale blue coat dress might have looked extra familiar though, because Kate basically wore the same thing to Meghan Markle and Prince Harry's royal wedding in May, only in yellow.

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It's not uncommon to see Middleton in this silhouette, even with slight variation (take a brief scroll through her most memorable outfits and that becomes clear), but this level of sameness is odd even for her. Neckline? The same. Dress length? The same. Nude pump accessories? Also the same.

There were admittedly some teeny tiny differences (her blue dress had slightly shorter sleeves), but it takes more than a passing glance to notice them. Clearly Middleton's got her favorites, and this probably won't be the last time we see this kind of fashion on her.

Even at her youngest son Prince Louis's christening Monday, Middleton opted for a similar neckline in a dress that was made by, you guessed it, Alexander McQueen.

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If it ain't broke, don't fix it.