This is obviously the Duchess of Cambridge's favourite shirt

The Duchess of Cambridge wears tiaras and couture, but just like any other woman, she relies on one casual wardrobe essential. In her case, it’s striped shirts.

On Wednesday, Kate greeted London Marathon runners before Sunday’s race wearing black skinny jeans, white Cotu Classic Superga sneakers, and a £160 Luisa Spagnoli knit white sweater with blue and red stripes. She wore her brunette hair down and added a touch of glam with £495 Kiki McDonough citrine drop earrings.

While science and fashion can’t seem to agree on whether stripes are a flattering pattern, the Duchess clearly loves the classic print.

She owns three different styles of the ME + EM Breton top — at a 2014 polo match in Gloucestershire she wore a blue-and-white version with blue skinny jeans, while chasing one-year-old Prince George around the venue.

In 2015, six weeks after giving birth to Princess Charlotte, Middleton wore the cobalt-and-white top to the Beaufort Polo Club in Gloucestershire.

And later that year, Middleton dressed up a black-and-white version of the same top by wearing it with a black blazer.

In 2016, Middleton posed for British Vogue’s 100th anniversary issue in her first-ever magazine shoot. Within the 10-page pictorial shot in the Norfolk countryside, she leaned on a fence wearing a red-and-black striped T-shirt by Petit Bateau.

And in 2013, while attending a SportsAid workshop at the Olympic Park in London, the Duchess wore a white-and-blue Ralph Lauren Tori Breton-striped top, blue Stuart Weitzman Corkswoon wedges, and a navy blue Smythe One Button Blazer.

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