No need to look for the addresses. This was a must before all meals when we couldn't get to water. Backpack - to store cameras, ponchos, etc. in. I can't tell you how many people I overheard saying to one another, We should have gotten one too. Beach Towels - For the water parks.
Disney resorts provide towels for the pools.
Fanny pack for you and the kids. Those little orange and white envelopes. Kleenex Laundry Detergent - Rather than paying high prices for a small box of laundry detergent, bring some from home in a resealable plastic bag. Doing laundry during your trip also allows you to pack less clothing. It can be a real hassle getting prescriptions filled long-distance, and might take a day or two to get hold of your Doctor to approve them.