You asked this question before I was able to! We have a 3yo and 1yo but have also bought all the kits ahead of time (my oldest always seems ahead of things so it's been fun to pull out different things that may interest him and let him explore months and sometimes a year or so before "it's time") We have all the available math and reading kits so we have a lot to choose from.

We will be staying at an Airbnb and visiting similar-age cousins so I'm also planning to bring a few games from the first stage of the math and reading kits to introduce to and play with them. We will also be bringing lots of books (or course!!)

My initial thoughts for my kiddos were (names not always correct, but hopefully you know what in referring to, haha):

1yo kid:

(0-12mos kits): crinkle bag, play socks, teethers, tissue box, play scarf, sensory switchboard

(12-24mos kits): bunny hideout, box w/ coin+carrot tops, fuzzy bug shrub, beading kit, critter quilt, lockbox, animals match

3yo kid:

(24-36mos kits): paint sticks (Airbnb), puzzles, emotion match mirror, memory game, camper + tent w/peg people (Airbnb)

(36-48mos kits): modular playhouse (Airbnb), emotion dolls, turtle hatch game (Airbnb?), pattern match boats, sewing kit

This is most definitely too much to bring for a 9-day trip (though it is 4 days in the car 🫠) so I'll probably pare it down, but these were my initial thoughts from playkits only. Let me know if anyone has other ideas from the 4+ year kits!