Friday saw Princess Eugenie join her cousin, Prince William, at the Duke of Westminster's Cheshire wedding.
For the ceremony, the Princess opted to wear a wedding-worthy silky green dress, but ahead of the evening celebration, the royal changed into an outfit that might have raised a few eyebrows.
Princess Eugenie's evening outfit
Sarah Ferguson's daughter pulled out all the stops when it came to her outfit for the evening celebration, switching from her pastel-hued dress to a black number – which may come as a surprise to wedding-attire etiquette experts, as black is a colour guests are often dissuaded from wearing.
Princess Eugenie certainly looked beautiful in her second outfit, with the black dress featuring delicate floral embroidery and a daring thigh-split, but black is an unorthodox colour for weddings, mainly due to the sombre associations the shade has.
Of course, wearing black is not as frowned upon as wearing something white, but sticklers for tradition were likely bemused by the royal's choice, especially since her fellow guests chose pastel yellow and rainbow ombre dresses.
HELLO! spoke exclusively to a guest at the wedding, who told us an outfit change was encouraged. "We had to have outfit changes ready for the reception," they revealed. "I had five different outfits to choose from and I didn't know what I was going to wear until the night before!"
Princess Eugenie's accessories
The royal certainly thought hard about her outfit, as she beautifully coordinated her shoes and bag, opting for gold metallic for both, with her strappy stilettos the centre of attention due to the thigh-split in Princess Eugenie's dress.
Flying solo
Princess Eugenie and Prince William were the only senior royals in attendance on the big day, with Eugenie's husband Jack Brooksbank notably absent from the soiree.
We doubt the royal would have been denied a plus-one, so perhaps Jack was working or looking after their two sons, August, three, and Ernest, one.
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Eugenie took riding solo in her stride, saying she was "fifth-wheeling" with her friends, who attended as couples.
The Princess reportedly drank Modelo beer straight from the bottle, and ordered macaroni cheese – we love a down-to-earth royal! She reportedly loved the pasta dish so much that she took a photo in order to replicate it at home – a treat for her young sons!