The 36-year-old actress will be celebrating the holidays with the royal family -- and breaking tradition! Kensington Palace confirmed to ET on Wednesday that we can "expect to see the Duke and Duchess of Cambridge, Prince Harry and Ms. Markle at Sandringham on Christmas Day."
Sandringham is the royal estate in Norfolk, England, where the royal family traditionally celebrates the holiday. Royal expert Katie Nicholl says the invitation is unprecedented.
"It's always been the case in the past that only married couples attend Christmas at Sandringham," Nicholl tells ET. "She really will be a first in being a royal fiancée at Christmas dinner."
"It's a big deal because it's incredibly unusual. Yes, they are engaged, but Meghan doesn't have that all-important wedding band on her finger," she explains. "I think that she might well be the first royal fiancée to be invited to Sandringham for Christmas. The queen has really gone above and beyond and she's done that very simply to make Meghan feel welcome and to keep Harry happy."
By comparison, in 2010, Prince William was engaged to Kate Middleton during the holidays, yet she did not attend the Christmas celebration.
"It simply wouldn't have been protocol for Kate to have gone," explains Nicholl. "Yes, they were engaged, but she had always made it clear that she wanted to spend her last Christmas before she got married with her own family."
"I suspect that if William would have asked for Kate to be allowed to go, I'm sure the Queen would have allowed it," she continues. "But that wasn't the case. It was a different scenario; it was a different set up. Kate didn't want to be at Sandringham for that first year before she got married."
Christmas is a very intimate family affair for the royal family, and according to Nicholl, the Queen is "very strict about who is around her Christmas table."
Among the possible reasons that the Queen may have pushed the boundaries for Markle is that the Suits star is giving up a lot to be with Prince Harry, including her American citizenship, her home and career.
"I think we're seeing a lot of signs that the royals are becoming, perhaps, a little bit more accessible," Nicholl adds. "Opening up the grounds of Kensington Palace after last night's [Star Wars] premiere is just one example, but there have actually been quite a few this year."