01/19/2018 10:22 EST | Updated 01/19/2018 10:23 EST

Meghan Markle Takes A Style Cue From Princess Diana And Kate Middleton

She's becoming more royal by the day.

AFP/Getty Images

If you're going to be a member of the Royal Family, you may as well start dressing like them.

Meghan Markle, who is marrying Prince Harry this May, took a style cue from her late mother-in-law, Princess Diana, and her soon-to-be sister-in-law, the Duchess of Cambridge, when she and Prince Harry stepped out in Cardiff, Wales, on Thursday.

For the occasion, the former actress wore a black Stella McCartney coat, Hiut Denim jeans, Tabitha Simmons velvet booties, and a cozy scarf. Underneath her winter ensemble, the 36-year-old sported a plaid off-the-shoulder jacket by Theory, which she styled as a top.

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Prince Harry and Meghan Markle during a walkabout at Cardiff Castle on Jan. 18, in Cardiff, Wales.

Although she probably didn't make the link between her outfit and the Royal Family, Markle's plaid top was a subtle nod to the women in the family.

The Duchess of Cambridge is in fact a fan of plaid, more recently having worn the pattern on an L.K. Bennett coat this December, and on an Alexander McQueen dress-coat in 2014.

Samir Hussein/WireImage
Catherine, Duchess of Cambridge attends the Children's Global Media Summit at Manchester Central Convention Complex on Dec. 6, 2017.

And 30 years ago, Princess Diana wore a plaid oversized blazer over a white turtleneck.

The $250 jacket was also a tribute to Prince Harry, as the design was made from the Prince of Wales check, in reference to Harry's full title, Prince Henry of Wales, reports Hello.

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Prince Harry and Meghan Markle watch a game of Jenga during their visit to Star Hub on Jan. 18, in Cardiff, Wales.

Once again, Markle decided to ditch royal protocol and wear her hair in a messy bun for the occasion. The first time she wore a decidedly un-royal hairdo was when she and Harry made their first joint engagement of 2018 last week.

She also made another royal faux-pas by giving out her autograph to a young girl who had reportedly been waiting for hours to see the couple.

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Princess Diana in 1988.

Members of the Royal Family are discouraged from signing autographs because of the risk that they might be forged, and for the more practical reason that once they start signing autographs they'll have to start handing out more, which would hold up their engagements.

But there's plenty of time for Markle to learn the royal rules before her and Harry's May 19 wedding. After all, there's a lot to memorize, from when to curtsy and to whom, an inner knowledge in the workings of the government, arts, and media, and when she can take selfies (answer: never).

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