It may not be her first time at Sandringham for Christmas, but Meghan is still getting advice so she is not wrong now that she is Duchess of Sussex. Meghan will join her husband, Prince Harry, on the Queen's property in Norfolk, after spending Christmas at Sandringham last year, despite not being married to Harry at the time. The couple will attend the Church of Santa Maria Magdalena with the Queen, Prince William and Kate, and other members of the Royal Family for a Christmas day, before returning to the royal estate for dinner and traditional games.
But before the Christmas Day activities begin, Meghan and Harry will receive a very important phone call.
Queen's Equerry informs the royal family a week before Christmas at what time they should arrive at Sandringham House and in what order.
As with official events, the royal protocol insists that the Queen and Prince Philip are the last to arrive, since they are the oldest members of the Royal Family.
Guests are placed in order of seniority and importance, with the youngest royals arriving first.
It is likely that Prince Harry and Meghan arrive with Prince William and Kate, followed closely by Prince Charles and Camilla, the Duchess of Cornwall.
All members of the royal family line up to welcome the queen and Prince Philip.
A similar process takes place in public on Christmas Day, when the members of the royal family stop outside Santa María Magdalena to bow and bow before the Queen when she leaves the church.
After lunch, the royal family will exchange gifts, but there are also rules about it.
Gifts should not be expensive, and often become a novelty, are joke gifts, with Kate, the Duchess of Cambridge, even a year buying Prince Harry a "grow your own girlfriend" kit.
Once the gifts have been exchanged, the members of the royalty decide on a game of Charades, one of the Queen's favorites.
The Queen and Prince Philip will stay at Sandringham until the beginning of February, and the decorations will remain in place until then.
In addition to the Cambridges and the Sussexes, the Yorks will be present.
Princess Beatriz and Princess Eugenia attend the festivities every year with their father, Prince Andrew.
But Sarah Ferguson does not receive an invitation after divorcing Andrew, even though they both live together.
She revealed earlier this month that she watches her children in the news every year.
It has also been suggested that William and Kate could miss the Christmas celebrations in Sandringham to go with Kate's parents.
Her brother James Middleton said last week that Christmas is a time to "regroup" with the family, implying that he and his two sisters Kate and Pippa could meet.
The Duke and Duchess of Cambridge also separated from the royal family to spend the festivities with the Middletons 140 miles away in Bucklebury in 2016.