Thanks for all of the suggestions....I just had not been able to find them around here in the stores I normally go in often (Wal-Mart / Target), but I'll keep looking.
I'm not sure the Camelbak is for me. I'm looking for the straps so we can each have one in addition to our fanny packs, and hopefully mom won't have to lug that backpack around like I did last time! I'm really trying to travel light around the parks this time.
Thanks for all of the ideas!