The sprouts may disintegrate, the roast potatoes may burn, the pudding may set fire to the curtains, Uncle Walter may fill the house with noxious fumes, and Auntie Doreen may sing, but, well, what do you expect at Christmas?
Look, the sniping resentment between your brother and Cousin Jack will probably evaporate when confronted with the ferocious attack on your sister-in-law by Auntie Fiona; and Grandad's decades-old feud with Great Uncle Bob won't last for long because they'll both fall asleep after dinner.
And what will the incinerated currants on the cake matter when they're hidden under a tooth-rotting layer of glutinous icing? It's not as if anyone's going to want to eat it, anyway.
So banish your nerves and look on the bright side: if all else fails you can always take the fuse out of the dishwasher plug, shut yourself in the kitchen, and spend a blissful couple of hours washing up.
Thing Not To Do Today: be nervous. This word comes from the Latin nervus, meaning nerve. Before that it was probably something to do with the Greek neuron, and before that probably something to do with the Sanskrit snāven, which means sinew.