It will be the biggest gathering of the Royal Family in decades.
The Queen and Prince Philip have invited 27 of their nearest and dearest to celebrate Christmas at Sandringham, their private country retreat.
From Friday afternoon more than two dozen royals will descend on the picturesque Norfolk estate. They will include the Duchess of Cambridge, Katherine Middleton, who will be enjoying her first royal Christmas, as will Zara Phillips's disgraced England rugby player husband Mike Tindall.
But the sheer volume of guests is causing something of a headache for staff at the mansion, who have not catered for such large numbers over the festive season in years - an issue many families face at this time of year, albeit on a less grand scale.
As a result, royals at the "lower end" of the pecking order are being shifted into the servants' quarters.
They are said to include Viscount Linley, Queen Margaret's son, his wife Serena and children the Honourable Charles and Margarita Armstrong-Jones.
His sister, The Lady Sarah Chatto, her husband Daniel and children Masters Samuel and Arthur Chatto are also expected to find themselves relegated to what is known as the "Bachelor Wing", so-called because it normally houses many of the single men on staff.
This part of the house is traditionally used by servants from F (Food) Branch of the Royal Household - all those responsible for the preparation, cooking and presentation of food for the Royal Family and their employees, including chefs, kitchen porters and the like.
They will now have to pack up their belongings move into the footmen's bedrooms, prompting grumbling among those members of staff who will now have to double up and share.
One said: "Sandringham is a large country house by anyone's standards but they are going to be crammed in like sardines this year.
"What with all the new husbands, wives and children, it's the biggest royal gathering anyone has seen in years."
Set in nearly 600 acres of woodland, Sandringham has been the private home of four generations of British monarchs since 1862. The house itself has always been rather small by royal standards and many a visitor has remarked about the particularly "cramped" living quarters.
Like most matriarchs, the Queen is a stickler for tradition and asks that her guests arrive from the morning of December 23 onwards, with Prince Charles and the Duchess and Cornwall being two of the last to arrive.
The Royal Family follows the German tradition of opening its presents on Christmas Eve before changing into black tie and evening gowns for a candlelit banquet. At around 10pm the women adjourn, leaving Prince Philip to serve port or brandy to the men.
On Christmas morning they attend the service at St Mary Magdalene, the church on the estate. This year the Duke and Duchess of Cambridge are expected to attract the loudest cheers from well-wishers.
Back at Sandringham, they settle down to a traditional turkey lunch at 1pm before gathering around the television to watch the Queen's Christmas broadcast at 3pm.
The evening is spent relaxing, playing games and watching television, much as in other households across the land, and on Boxing Day Prince Philip traditionally organises a shoot.
Contrary to reports, Katherine's sister Pippa hasn't been invited to join in the fun but the duchess is expected to meet up with the rest of the Middleton family as soon as possible.
- DAILY MAIL