When my kids were really little, I used a Vera Bradley mini backpack type bag. When I didn't need to carry around diapers, I used the Vera Bradley mini hipsters to carry my daughter's Epi-pen & Benadryl. But we had the stroller to keep our water bottles in. We're not using a stroller on our upcoming trip, so I'm thinking this time I may get another mini backpack type bag or a larger crossbody bag to carry our water bottles.