Texas

I am filling out a legal form: "DIRECTIVE TO PHYSICIANS ON BEHALF OF A MINOR"

1. I am married, do we need two forms, one each for me and my wife for our child, each with duplicate details?

2. I assume the two witnesses cannot be blood or family, but do they have to be someone I know? Can I just use other people at the location where I obtain Notary services?

3. Do I need to file the directive with some authority or office in Texas, or just keep in with my important papers?

Thank you,
Michael