At what age is a person vested with the rights of a citizen? We have a patchwork of ages for drinking, driving, owning long guns, handguns, age of marriage without parental permission, signing contracts, criminal records & charges, etc. Also in some states, one can become “emancipated” by the courts at an early age if one is mature enough and doesn't have good parents.
Perhaps, the question should expanded by additional litigation, so we determine whether certain age definitions are state or federal issues.
Ponder this.
Under Obamacare, that age is now 25 (when you go off your parents healthcare