Bug spray & sunscreen....water is fine. Also have him download the app, it gives great directions in order to find rides & wait times, dining, restrooms & more.
Should be alright.. I went this Thursday and I was able to take my camel pack which holds 2 liters of water and they refilled it all day long with ice free of charge..
You can take an empty bottle and they may refill, but it must be empty when you enter.
Exactly what ladebb said!
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