Kate Middleton might have passed a milestone when she married Prince William in April, but she is headed towards another hurtle - Christmas.

Despite the fact that the lovely duchess has been dating Prince William for ten years, she has never attended Christmas weekend at Sandringham manor - the queen's sprawling 20,000-acre estate complete with an 18th century castle. Catherine will learn quickly that this is not like any Christmas she has had, said a source.

Middleton's family will not be invited to the Christmas Eve or Christmas Day festivities. Pippa is, however, invited to Boxing Day. Kate must conquer alone. 

Us Weekly got all the info on the holiday weekend - from outfit changes to etiquette. She'll pack a lot, Middleton's former stylist Nikki Pennie told the magazine. Five or six spare dresses.

Here are the details on what will surely be a Christmas to remember.

Christmas Eve

Presents are first on the itinerary for Christmas Eve. Although this might sound classically merry, royal Christmas follows a strict pattern, said Robert Johnson, author of William & Kate: The Love Story, to Us.

The family will gather around the tree where white linen placards designate where each particular present should be placed. Tradition has been to exchange novelty gifts, a source told the magazine. Harry and William once surprised Prince Philip with a whoopee cushion. However, another source said that Kate should steer clear of gag gifts since she's not on joking terms with Her Majesty yet.

After gift-giving come the cocktails. It's a black tie affair, said Johnson. Gin and tonics are served, though the queen, Prince Philip and Prince Charles prefer dry martinis, according to Us. Following that will be the sit-down meal, where Kate must hold her own during the dinner conversation. Dinner usually consists of shrimp, lamb or locally shot game.

Kate must wear different outfits for gift-opening, cocktails and dinner. 

Christmas Day

The royals rise to stocking's, stuffed with small gifts, at the feet of their beds, Johnson told Us. After an English breakfast spread, the family will go to the Church of St. Mary of Magdalene on Sandringham's grounds. There is a specific formation based on hierarchy that Kate must follow.

Once mass ends, they will lunch at 1 p.m. They eat a giant turkey with all the trimmings. Then they watch the queen's taped speech to the nation at 3 p.m. After this, comes relaxation. The queen favors family board games to be played during downtime, Johnson told Us. Though Monopoly is banned because it gets too vicious!

Boxing Day

She can relax because the queen will not be around her that much that day, the source told Us Weekly. Pippa scored an invite from the queen to this event. Though it's normally restricted to royals, the queen invited Pippa. She's aware of how difficult it is for a new bride to cope with the Christmas traditions. She hopes to make Catherine feel at home, she another inside source.

The Boxing Day contest involves a pheasant shoot on the grounds of the castle. The winning team will bag the most birds. Catherine is not the best shot, but she's leaving nothing to chance. She has taken lessons with Prince Charles' private hunt attendant, said Johnson. And she has become much more confident with a gun.

After the final lunch at Sandringham, William, Kate and Pippa will head to the Middleton home in Bucklebury. This trip is important for William, said a source. He loves spending time with the Middletons, so this will  be as much as a treat for him as it will be for her.

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