Princess Anne is not shy about pushing the boundaries with her fashion choices – just look back to 2005 for proof.
The Princess Royal reigned supreme in the style stakes when she attended her brother Prince Edward and his wife Sophie Rhys-Jones' nuptials in 1999. As she chatted to Sophie's brother David on the way out of St George's Chapel, Windsor, Anne was pictured in a mint green wedding guest ensemble including a structured dress layered underneath a cropped jacket in the same soft pastel colour.
Her hair had been swept up into a neat chignon and topped with a bright emerald green feather – an alternative to the traditional fascinators and hats Sophie and Edward had asked guests to avoid.
Accessories-wise, Anne added pearl earrings, a four-strand pearl necklace and more bridal white accessories. A milky clutch bag was balanced in her hand while ivory court shoes could be seen underneath the hem of her skirt – not unlike Sophie's bridal heels.
The bride's footwear featured a V-shaped cut in the bridge and a mid-height heel, visible as she walked down the steps hand in hand with her new husband in a Samantha Shaw wedding dress.
This was not the first time Anne opted for a white wedding guest look – which is considered a fashion faux pas. White is considered one of the few colours off-limits for wedding guests to prevent upstaging the bride.
Anne didn't seem fazed about the unwritten rules when she attended Lady Rose Windsor's nuptials in 2008 in a knee-length frock with a ruffle hem and a yellow floral print. Despite once again wearing a pair of snowy heels, she added a touch of colour with her lemon hat.
Royal wedding rules
Anne wasn't the only one to bend the rules at a royal wedding. The Princess of Wales similarly wore a rebellious white dress to the wedding of friends William van Cutsem and Rosie Ruck Keene in May 2013.
Kate, who was heavily pregnant at the time, wore a black and white polka dot smock dress with a cropped jacket and towering heels.
Meanwhile, royal enthusiasts may already know that outfit protocol stipulates that guests' shoulders and toes should be covered during a church service.
As Chloe Madeley arrived for Meghan Markle and Prince Harry's wedding ceremony, she was pictured wearing a strappy gown having taken her jacket off during the warm coach ride.
Richard and Judy's daughter later said: "[I thought] it’s fine, it’s not a big deal, nobody will care. Yes, people definitely cared. People were like, ‘You’re offending the House of the Lord, I was like, ‘Oh my god, oh my god, I did not need a religious war’. But, you know, it’s OK, lesson learned."
On the same day, Meghan's Suits co-star Patrick J. Adams was pictured with his wife Troian Bellisario in open-toe shoes.
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