The Prince and Princess of Wales are set to make their annual visit to the Irish Guards to mark St Patrick's Day on Friday, with Kate expected to maintain her tradition of wearing green to the patriotic event.
But some royal fans may remember that there was one year when the Princess broke her own fashion rule, by opting out of her usual Irish green outfits and wearing a grey Catherine Walker coat instead, teamed with a brown hat from Lock & Co.
It was 2015, and Kate was pregnant with Princess Charlotte at the time – with most reports suggesting that the coat was the most comfortable in the later stages of her pregnancy. The following year, she missed the St Patrick's Day parade altogether, choosing to stay at home with the young Prince George and Princess Charlotte instead.
Kate opted out of wearing green at 2015's St Patrick's Day event
Kate has been attending the annual event since 2012 (except 2016), and other than the one exception, has always worn a tailored green coat – teamed with a hat in black, brown or green.
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The jury's out on what the Princess will wear to the 2023 parade, though most royal fashion fans would be willing to bet that she'll stick to green from now on. Aside from its patriotic relevance, the royal loves to wear the verdant shade regardless.
Except for the one time, Kate has always worn green on St Patrick's Day
For 2022's parade, which came after two years of cancellations due to the coronavirus pandemic, Kate wore an elegant Laura Green London coat, which featured her favourite high collar neckline and a belted waist. See the happy footage from the event here:
WATCH: Princess Kate stuns in green at St Patrick's Day 2022
At other appearances, the Princess has opted for a military look in her go-to designers such as Alexander McQueen or Catherine Walker - she has also been known to wear high street in Hobbs, or another of her favourites, Emilia Wickstead.
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