Keeping track of kids medical information can be extremely overwhelming. When they are grown and need to know important information from their childhood... you simply cannot remember everything.
I would gather and download all of their information to keep in one safe place. This can be updated annually or on need basis. This includes a medical timeline I would keep updated or give you the template to do on your own. This will be a great way to also teach them how to keep track of their information . This is all kept on a convient thumbdrive organized into folders labeled in a way that you prefer.