Just get a standard first aid kit into each one should be fine. Back home mine also had a sewing kit, cash, some chocolate (trail mix is good too), a tool for breaking car windows, a can opener, utensils for cooking and eating, and a collapsible water bottle with purification tablets. Here I put in a spare leash as well. Prescription medications are important, but that will be something for people to handle on their own. Phone charger's probably a good idea too, and a power bank.