Catherine, Duchess of Cambridge, is believed to have changed outfit five times on Christmas Day alone. Photo / Getty Images
Christmas can be festively fraught for most families, but the Windsors have long outdone us all in the seasonal stress stakes.
From squabbles over who will accompany the Queen to church on Christmas Day to irate royal relatives being crammed into cramped servants' quarters, Sandringham has played host to many of the monarchy's ups and downs over the years.
Now with rumours of a rift between the Cambridges and the Sussexes, newbies like Princess Eugenie's husband Jack Brooksbank thrown into the mix and the small matter of Meghan's pregnancy set to dominate proceedings, Christmas with the royals could prove to be quite a cracker this year.
Will Doria turn up at the last minute? Will Harry go on the pheasant shoot after all? And what will Kate give Meghan in the Secret Santa?
Here's our ultimate A-to-Z guide to everything you need to know about Christmas at Sandringham.
A is for... arrivals
You don't just turn up to Christmas at Sandringham - you follow a strict protocol, with royals arriving in order of seniority, from the most junior first. Afternoon tea is served at 4pm, usually involving cake and scones alongside finger sandwiches: crusts off, served in squares, washed down with Earl Grey tea.
B is for... breakfast in bed
On Christmas Day, the ladies generally opt for a light breakfast of sliced fruit, half a grapefruit, toast and coffee delivered to their rooms. The Queen's tray is delivered at exactly 9am. The male royals, meanwhile, come downstairs to the dining room for a full English breakfast.
C is for... change of clothes
Before her first Christmas at Sandringham in 2011, Kate admitted she was feeling nervous about the wardrobe pressure, confiding to a fellow guest at a charity event that she would have to change five times on Christmas Day alone. The Duchess of York once remarked that she was obliged to wear seven outfits in a 24-hour period.
D is for... duchesses
With rumours rife of a royal rift between Kate and Meghan, all eyes will be on the sisters-in-law as the tuck into turkey and all the trimmings. The Queen is in charge of the seating plan, with adults sitting at the main table while the children eat Christmas lunch separately in the nursery at 12.30pm.
E is for... estate
Set in 8,000 hectares, Sandringham House first came under royal ownership in 1862 as a country residence for the future King Edward VII. Royal Christmases used to be celebrated at Windsor Castle until 1988, when the castle was rewired and the festivities returned to Sandringham.
F is for... food
Although the royals are said to "graze" rather than wolf down their meals, there is no shortage of food. Afternoon tea on Christmas Eve is followed by a three-course, black tie dinner at 8.15pm.
G is for... Granny and Grandpa
At 92 and 97 respectively, it is no wonder the royal Christmas tends to revolve around the Queen and Duke of Edinburgh these days. Her Majesty always travels up to Sandringham the Thursday before Christmas Day, taking the train from King's Cross to King's Lynn, to the delight of fellow passengers.
H is for... Heiligabend Bescherung
The royals follow the German tradition of opening their presents on Christmas Eve. The gifts are piled on trestle tables alongside name tags. This is one of the few times that the children will be permitted to join the adults.
I is for... in-laws
Although Meghan's mother Doria Ragland is thought to have been invited to spend Christmas at Sandringham, she is understood to be celebrating in Los Angeles, in anticipation of travelling to London in the spring for the arrival of her first grandchild.
J is for... joke presents
Princess Diana long ago realised what a minefield giving presents can be to the family that already has everything. Generously, she bought cashmere and other luxury items for her in-laws, only to discover that joke gifts - and the cheaper the better - were the order of the day.
K is for... Kate
Who will be missing out on a special Bucklebury Christmas this year as her parents, Michael and Carole, play host to her sister Pippa, husband James Matthews and their new baby, Arthur, born in October. It is also Prince Louis's first Christmas.
L is for... lunch
The royals' Christmas lunch is traditional, with a roast turkey - from local butcher Scoles in Dersingham - taking centre stage. It is the one day of the year that the head chef is permitted to enter the dining room, to carve the bird at the table. Once he's finished, the Queen will offer him a tot of whisky.
M is for... more food
An evening buffet is laid out in the dining room at 8.15pm on Christmas Day, although there is not a sausage roll or Quality Street in sight. Instead, traditional English cuisine such as a stuffed boar's head on platters, ox tongue and boiled and roasted hams are served. A small circular table is laden with the Queen's favourites, Bendick's Bitter Mints.
N is for... Norfolk
The county is also home to William and Kate's retreat, Anmer Hall, where the Sussexes stayed with the Cambridges last Christmas. It is thought they will again, despite reports the Queen has invited Harry and Meghan to the "big house".
O is for... other halves
Who are traditionally not invited to Christmas at Sandringham until they are married to members of the royal family - although Meghan broke the mould by getting the call-up last year, even though she was merely engaged to Harry.
P is for... pudding
Doused in brandy and decorated with holly, the royal Christmas pudding is carried into the dining room by the Palace steward and lit in front of everyone. Although full of alcohol, no coins or trinkets are added for fear of a royal choking.
Q is for... Queen's Speech
Everything stops at 3pm for The Queen's Christmas Broadcast. First delivered by George V in 1932, each address carefully reflects current issues and concerns, and shares the Queen's reflections on what Christmas means to her and her listeners.
R is for... retiring
The Queen normally doesn't go to bed until midnight, and no one may leave the Christmas festivities until Her Majesty calls it a night.
S is for... shoot
After a hearty breakfast on Boxing Day, it is tradition for the men to go on a pheasant shoot arranged by Prince Philip. It is likely Harry will attend, despite reports he had pulled out on animal-loving Meghan's orders.
T is for... tat
Although the royal Christmas table features elaborately folded starched white napkins, a silver candelabra with lit candles, wine decanters and red and gold crackers at each setting, there is no shortage of festive "tat" elsewhere at Sandringham, with tinsel and gaudy trinkets aplenty.
U is for... under the mistletoe
There is little room for festive friskiness at Sandringham, with royals forced to share rooms with their children in the servants' quarters, in what is regarded as the smallest of all the royal residences.
V is for... vino
Although not a drunken affair, the royals' Christmas festivities are quite boozy. Martinis are served before the Christmas Eve dinner, and then Prince Philip is in charge of the after-dinner liqueurs. Christmas Day drinking begins as soon as the royals have returned from church, when the Queen will request a pre-lunch gin and Dubonnet. India pale ale fan Philip will enjoy a beer as others are offered a glass of champagne.
W is for... walkabout
The highlight of every festive royal fans' Christmas: the walkabout to St Mary Magdalene Church for the 11am service has long proved a huge draw. Last year, single mother Karen Anvil made a splash by taking a better photograph of the Fab Four than any of the assembled paparazzi.
X is for... X-rated
With joke presents all the rage among the royals, Harry once gave the Queen a bath cap with "Ain't life a b----?" emblazoned across it. Granny apparently howled with laughter, as did relatives when Kate presented Harry with a "Grow Your Own Girlfriend" kit.
Y is for... Yoga
Meghan won't be the only one doing the downward dog after two days straight with the royal in-laws. Charles and Camilla - also said to be keen on the ancient Indian practice - like to escape soon after the festivities are over, with Camilla retreating to Ray Mill, her house in Wiltshire, to spend time with her children and five grandchildren.
Z is for... Zara Tindall
No one quite knows how Zara and Mike Tindall have managed to wangle their way out of Christmas at Sandringham in recent years, to spend the festive period in Australia instead. The couple are once again due to attend the Magic Millions race series on the Gold Coast in January.
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