They must reside with someone who is their parent or legal guardian, or to a close family member to whom the responsibilty for their upbringing has been legally delegated by the parent(s) or legal guardian(s).
No, a legal guardian must be of the legal age that is required by the state in which the minor children reside. The legal age to become a guardian of minor children is not necessarily the same as the state's age of majority.
Anyone can bring a minor to a doctor. Getting permission for treatment unless life threatening is only legal by parent or guardian or the President of the United States, since he is the only one that can on the spot change the laws.
A legal guardian, by definition, is going to be at least 18. A guardian is the single adult that has been given legal authority to take care of a minor. It isn't any person that is older than the minor.
The state of Florida prohibits the piercing of a minor without the written, notarized consent of the parent or legal guardian. Consent may also be a parent or legal guardian accompanying the minor to receive the piercing