Update:
After a few weeks of waffling back and forth over Toy Story (Buzz, Woody, Jesse, Aliens or Potato Heads) , Jack, Sally , Lock shock and Barrel and realizing I have absolutely no crafty skills and even less patience (not to mention no time!) I have decided (sorry fam, no vote!) we will do the following:
Mom (me): Pooh
Dad: Eeyore
DS13: Christopher Robin
DD10: Piglet
DS7: Tigger
We will get character tees from
Amazon along with the costume accessory pieces. I was chuckling the entire time I was researching, as DS13 is 6'2" and about as far from Christopher Robin as you can get. His costume will consist of a yellow polo shirt, blue shorts and tall white socks
DH will be just about the most hilarious Eeyore, picture a surly, bearded, heavily tattooed donkey!

I'm dead already!
My pooh costume will be golden yellow chino shorts and a red Pooh tee shirt, with sequin Pooh ears with a big red bow (ok, Minnie ears, but whatevah!)
Piglet will be a light pink leotard with belly stripes, a pink tutu (of course!), pink tights, legwarmers and piglet ears.
Tigger will consist of a Tigger striped tee and the costume accessory kit with black athletic shorts. My little one will be the most vocal about any discomfort, so we'll call it good!
We leave 3 weeks from tomorrow and I still have so much to do! I'm freaking out! Time to start the checklist!