If you encounter a signer who is a minor, the fact that he or she is underage does not preclude you from proceeding, but there are issues to keep in mind.
If the minor cannot produce a valid driver’s license, passport or other acceptable ID, then you my have to rely on credible identifying witnesses. The witnesses should not be the minor’s parents or guardians.
To determine willingness, make a commonsense appraisal by engaging the minor in a conversation. The minor can demonstrate awareness by clearly explaining the purpose of the document. Finally, the minor (or adult companions) should satisfactorily prove that he or she has the authority to sign. It’s a recommended practice to have the minor print his or her age next to the signature so that information is readily available to any relying party.