Hi, Unique! Welcome to the Disney Parks Moms Panel!
How exciting it is to help you plan for your very first Walt Disney World Resort trip! I can't even imagine your excitement as the day comes closer! Congratulations on planning things in advance!
Every Guest is allowed to take a backpack into the Theme Parks, so there is no need to worry about that. As long as they're
not larger than 24" long x 15" wide x 18" high, you will be fine.
My advice, though, is to keep your weight to a minimum. Theme Park days can be long, and there is quite a lot of walking to be done, so I'd pack the essentials in one backpack for the adults to take turns carrying. I'd prioritize sunscreen, rain ponchos, refillable water bottle, any medicine that's needed, small snacks, wallets, an extra battery to charge the phone, a cable and hats for the whole group.
Some people also like to bring more substantial meals and spare clothes for the kids, and my advice is to keep those on a bag that can be carried under the
stroller or on a
rental locker so that you don't have to take the extra weight during the day.
I hope this advice helps you plan for fantastic days, Unique! Let the Disney Parks Moms Panel know if you want more help. We're always here to help!
May the magic be with you,
Julie