Medical Supplies
Aside from water and food, you should also keep a basic supply of first aid materials on hand. Having rubbing alcohol or peroxide and Band-Aids will go a long way towards taking care of minor cuts and scrapes. The most basic ready-made first aid kit is better than having nothing, but you may want to add personal extras based on your family's needs.
Band aids of various sizes
Alcohol
Peroxide
Sterile gauze
Medical tape
Ace bandage
Pain relievers such as Aspirin and Tylenol
Cotton swabs
Tweezers
Antibiotic ointment or cream
Diarrhea medicine
Vomiting medicine