christmas eve dinner - Roasted ham, dauphinoise potatoes, green beans, red cabbage... mince pies & mulled wine
Most of this is fine, but just mashed pots rather than dauphinoise and do red cabbage in advance and freeze. I can see why you'd do the ham now though.
christmas day
breakfast - bacon sandwiches, OH or DM should make those while you get a chance to relax with DCs if you’ll be in kitchen all day
lunch - turkey/ham, roast pots & parsnips, stuffing, yorkshires, pigs in blankets, chipolatas, cauliflower cheese, sprouts, carrots, peas, gravy, cranberry sauce. pudding - xmas pud, trifle, yule log, and usually an m & s chocolate thing for the kids.
5 veg seems a lot, as does both pigs in blankets AND chipolatas. And 4 desserts. Unless you are making a lot of those in advance or buying it readymade.
Maybe cut back 1 veg and 1 dessert.
And get people there on Christmas Eve to do peeling of veggies, making breadcrumbs/stuffing, preparing cheese sauce etc – with music on and all chatting together. (And I presume someone else sets the table, and others do the washing up after every meal also?!)
Delegate starters to someone - and it can be completely different or even just smoked salmon on brown bread that the DCs could help plate up out of your way. (I know you said small, but anyone older than 1 could "help" plate up bread, 2 lettuce leaves, 2 cherry tomatoes, sliced salmon and some capers and a lemon wedge, when they have assistance - which grandparents would probably LOVE to help with!!).
Or a pot of soup that was made and frozen to just reheat, or something else simple to put together that others can do for you.
dinner - buffet type foods, cheeses, sausage rolls, xmas cake etc
Just throw at the table – good. And let others set it up, and heat up anything needing heating.
boxing day - breakfast - croissants, Get the DCs to roll those out to bake – great fun even for wee ones
lunch - cold turkey/ham, mashed potato, pickles. Make sure enough potatoes are peeled Christmas eve for this. And let others set it out.
dinner - buffet type foods, quiches, salads...puddings are leftovers from yest.
Again, anyone can set out the buffet
27th - breakfast - smoked salmon/bagels/scrambled eggs,
This is another that someone else can make
lunch - turkey & ham pie, pots and veggies
Again, set your willing helpers to peeling veg, chopping turkey/ham etc. And setting table, washing up, …..
Would a turkey curry make a nice change for you here? Easier (either a good jar, or an easy to make sauce, or there are good curry sauces that you could make in advance and freeze). Or a lasagne from the freezer (keep the leftovers for yourselves).