While the royals are probably pretty chummy with the Middletons by now - somewhere, we imagine the Duchess of Cambridge's head must be spinning. What if Prince Phillip says something out of line, what if Carole gets hammered, what if Pippa doesn't want to watch the Dr Who special. Oh the humanity!
Whether you are mother to the future king of not – that is pressure – so if you're having both sets of 'rents round for the first time, follow these tips:
Have a non-traditional Christmas
By that we mean, you have to choose which family traditions you incorporate and which ones you let slide. From when you open to pressies, to what time Christmas dinner is – have a plan and keep a balance of each family's traditions without feeling like you have to please everyone.
It's all about the kids
Children take centre stage on Christmas day – put them first, the rest is all white noise.
'Keep your focus on making the holidays pleasant for your children, and not on your own resentments and frustrations. You can work those out in therapy after the holidays,' says psychotherapist Tina B. Tessina.
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Begin new traditions and experiment – try playing some new games, if you are cooking – make something different that neither family usually have.
Don't get trolleyed
One drunk person ruins Christmas. Know the crowd, and match your drinking pace with others. You'll also want to be alert for when those zingers start firing about you having kids, or why you work so much.
Change the subject
Speak to your partner in advance about any topics that will light the blue touch paper and make sure the pair of you swiftly change the subject if conversation starts to head towards a danger zone.
Give people tasks
Make everyone feel included by giving them a job. Bring the wine, make a pudding, do the games – that way it is a team Christmas with everyone invested in it's success.
Got any advice to share with the group? Don't be shy...
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