Royal Family
Meghan Markle has to curtsy to Princess Eugenie when Prince Harry is not around. Pictured: Princess Eugenie, Princess Beatrice, Camilla, Kate Middleton, Markle, Prince Harry, Peter Philips, Autumn Philips, Isla Philips and Savannah Philips on the balcony of Buckingham Palace during Trooping The Colour on June 9, 2018 in London. Getty Images/Chris Jackson

Meghan Markle has to curtsy to Princess Eugenie during some instances.

The Duchess of Sussex became an official royal when she married Prince Harry, who is sixth-in-line to the throne. The next royal bride ranks ninth in the succession, but Princess Eugenie is also a royal by blood. As such, Princess Eugenie and Markle's situation as to who has to curtsy to whom is a little complicated.

According to former royal butler Grant Harrold, although Markle's husband has a higher rank than Princess Eugenie, there is a particular scenario when the new duchess needs to curtsy to the daughter of the Duke and Duchess of York.

"Technically Princesses Eugenie and Beatrice are blood royals," Harrold told Express. "Therefore, when The Duchess of Sussex is not with her husband she ranks lower than them as a non blood royal. The Duchess of Sussex would be expected to curtsey to any blood royals who are styled HRH."

Although Markle is expected to curtsy to Princess Eugenie at times, this may not happen in practice because the royal protocol has become lenient. "These days this rule is more relaxed," Grant added.

Princess Eugenie is set to tie the knot with her fiancé, Jack Brooksbank, in October. The couple will exchange "I do's" at St. George Chapel at Windsor Castle, the same venue where Markle and Prince Harry wed.

Princess Eugenie's wedding is expected to feature similar elements from the Duke and Duchess of Sussex's royal wedding. For instance, it might also be broadcasted like Prince Harry and Markle's.

"Although Eugenie and Jack aren't as high in the line of succession as Harry and Meghan, they're young and because of the likelihood of those famous faces, broadcasters would be missing a trick by not covering it," James Brookes of Royal Central told Express. "It's unlikely to secure the same viewing figures as Harry and Meghan's wedding, but people will still be interested as the Royal Family will be attending and that on its own draws a crowd."

However, Princess Eugenie's wedding gown will definitely be different from that of Markle. According to fashion experts, Sarah Ferguson's daughter will have a more contemporary bridal gown compared to Markle and Kate Middleton.

"I think we will see something more contemporary and fashion-forward than Kate and Meghan's dress choices and I'd imagine this will carry forward to the bridesmaids too and how she chooses to style her besties," said Kate Beavis fashion expert from Magpie Wedding about Princess Eugenie's gown.