Well first off, do you have reservations at Ft. Wilderness yet?? April is a busy time there and only 4 months away. That would be the first step. FW reservations are hard to get.
Once that is accomplished then enjoy!!
If you all are going to sleep in the same tent, make sure it states on the package that it sleeps at least 8.
Then I would also recommend bringing a smaller tent for your stuff.
Bring air mattresses
Bring a fan
Waterproof that tent thoroughly with seam sealer and fabric sealant.
Bring a ground cloth and a disposable ground gloth
Bring a tarp and cord to stretch over your site, or bring a screenhouse or some other type of shelter.
Are you planning on cooking at Ft. Wilderness?? (I don't, too many good restaurants at WDW).
No traditional fires allowed, but you can use charcoal in the grill provided and you can use propane stoves.
Bring at least two sets of toiletries so that the guys and the girls can go to the shower house at the same time.
Bring shower shoes
You need a power strip and at least a 40ft outdoor extension cord. (Camera, cell phone, alarm clock, etc.)
Here is a picture of my camp setup. (3 adults, each adult had their own tent).
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