I have visitation with my three grandsons, would I be considered the first guardian if they ever were taken out if their present home?

You haven't provided enough information to determine whether you would be considered as a guardian for your grandchildren in the event they were removed from their home for any reason.  If you believe there is neglect, abuse, or that the children are being subjected to unsafe conditions, you can report that to childrens' services. You also have the option to petition the court for custody if you believe the children are not safe with their guardians.  Assuming that a court has ordered the visits you currently have with your grandchildren, and that arrangement is working in the child's best interests, that would certainly be a factor for the court to consider when making any custody determination, although many other factors will be considered as well.