Welcome to the forum and the huge world of caravanning. Parksy's given you a good list. Here is another suggestion. Buy yourself a notebook and make lists that you can tick off as you load . for instance :-
MUM
Tops
Trousers
Skirts
bras
etc!
DAD
The same as above(not bras or skirts)
When you have listed all the clothes then list things like, tv, tv remote, cutlery etc.
For longer trips we print our caravan checklist off from the list that I've saved on my computer.
Most of our 'caravan stuff' such as crockery, utensils etc stays aboard the caravan anyway so all that we need to remember are the vital essentials such as beer, wine and erm.........., more beer.
Will start making list on computer, thanks for reminder about levelling blocks, must get some, and loo chems as well.
Been deserted by both Dads, one is doing Yorkshire three peaks with mates, the other is doing DIY, so Mums and toddlers going solo, Oh well more room for our stuff.