According to Grazia UK in 2018, royal expert and Majesty magazine editor-in-chief Ingrid Seward claimed the Queen would have her guests weigh themselves before and after Christmas lunch.
The Sun reports the tradition was started by King Edward VII in the 1900s and was carried all through Queen Elizabeth II's reign and was reportedly going to be continued by King Charles.
It is believed the tradition began so the monarchs could ensure the guests ate well at Christmas lunch.
The royal family spent their first Christmas without the Queen at Sandringham House, the royal winter residence in Norfolk. The stately home, about two-and-a-half hours north of London, is where the King and Queen Consort Camilla will spend the festive season and welcome in the New Year.
Like many families, their Christmas meal is the same every year.
"[They have] a salad with shrimp or lobster, and a roasted turkey and all of your traditional side dishes like parsnips, carrots, Brussels sprouts and Christmas pudding with brandy butter for dessert," former royal chef Darren McGrady revealed to Good Housekeeping.
"Afterward, they all go their own way before coming together again for afternoon tea and traditional Christmas fruitcake, then they gather again in the evening, where a buffet dinner with 15-20 different items awaits them. It's always a buffet with the chefs at the table carving."
In the past, the Queen served her head chef a drink, however, it is unknown whether King Charles carried on the tradition this year.
"Right before the Christmas buffet, the senior chef on duty goes into the dining room and carves the rib roast or turkey or ham and once he's done, Her Majesty presents the chef with a glass of whiskey and they toast," McGrady revealed.
"That's the only time the chef goes into the dining room and has a glass of whiskey with the royal family. It's one of the chef's favourite traditions."
On Christmas Eve, the family exchange their presents, which they lay out on trestle tables and swap after afternoon tea. Royal correspondent Phil Dampier told express.co.uk: "The adults exchange cheap joke gifts, with Harry once giving the Queen a shower cap with 'Ain’t life a b****' on it."
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