In 2018, millions of people watched as Meghan Markle married Prince Harry at Windsor Castle. On that day, many noticed her elegant wedding dress, understated makeup, and tiara. However, some royal watchers have noted that the Duchess of Sussex has refrained from wearing a similar headpiece since that day. Why hasn't Meghan mirrored Duchess Kate Middleton and Queen Elizabeth II when it comes to tiaras?

According to Insider, the former "Suits" actress is eligible to wear one due to the fact that "royal etiquette dictates you can do so whether you were born a princess or married into the royal family," but circumstances have not permitted her to wear one.

Royal commentator Richard Fitzwilliams discussed the confusion that followed the Duchess' decision to forgo a tiara during her trip to Fiji and Tonga with Prince Harry in 2018. At that time, Prince Charles had reportedly advised her to refrain from wearing one because doing so could seem "too extravagant."

"The dress code at Tonga and Fiji dinners were more relaxed in line with the personal preferences of Harry and Meghan in their tour of Oceania," the expert said. "At both Harry wore black tie. It would not have been appropriate for Meghan to wear a tiara at either," he elaborated.

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Recently, Middleton was seen wearing the Cambridge Lover's Knot tiara at the Queen's Diplomatic Reception at Buckingham Palace. At that event, the Duchess of Cambridge was also said to appear "not just like a future Queen, but almost as a current one" due to her wardrobe and relaxed presence at the event. It was also noted that she wore a particular item that is said to have given a subtle nod to Prince William's "personal fight."

As for whether or not royal fans will ever see Meghan wear a tiara again, Fitzwilliams reassured them that she will step out in one when the right occasion arises.

"She will undoubtedly wear them at appropriate future events," he said, adding, "though obviously this will depend on the duties she and Harry decide they want to undertake as senior royals."

Meghan Markle
Duchess Meghan Markle is pictured on Feb. 24, 2019, in Asni, Morocco. Kirsty Wigglesworth - Pool/Getty Images