Meghan Markle and her mother Doria Ragland will be "weighed" after their Christmas dinner as part of a bizarre royal tradition, according to a royal expert.

Royal expert and editor of Majesty magazine Ingrid Seward claims that each member of the royal family, including Meghan's hubby Harry and big brother Will, is weighed before and after tucking into their turkey dinner on Christmas Day.

Ingrid told Grazia that the Queen asks each of her guests to "weigh themselves" using a pair of antique scales when they first arrive at the Sandringham estate in Norfolk for the Christmas period.

But this is all to make sure guests are having a great time - and they're weighed to make sure they're being "well fed."

Meghan Markle, left and her mother, Doria Ragland, arrive at Cliveden House Hotel, in Berkshire, England, Friday, May 18, 2018 to spend the night before her wedding to Prince Harry. (Steve Parsons/Pool Photo via AP)

The tradition dates back to King Edward VII's reign in the early 1900s - and applies to all members of the royal clan.

As the festivities undeniably revolve around eating, the royal family first enjoy a turkey dinner with all the trimmings before indulging themselves in an afternoon tea complete with a "gargantuan iced cake."

And although the Queen appears to have bent the rules by inviting Meghan's mother to join the family at Sandringham (an honor which has never been bestowed on Kate Middleton's parents), this sacred tradition means that both Meghan and Doria will be weighed both before and after they leave the royal residence.

What's more, the Queen's guests are also expected to "enter the dining room in order of seniority."

After they are then seated, "the head chef carves the turkey" and "paper hats are donned, but not by the Queen."

In order to "make room" for their lavish afternoon tea, the royal family then walk the grounds of the Sandringham estate and enjoy a "candlelit dinner in the dining room" in the evening.

This article originally appeared in The Sun.