A person filing a claim on behalf of a claimant shall submit evidence of his or her authority to so act at the time of filing or at a reasonable time thereafter in accordance with the following:
A legally appointed guardian or committee shall provide the Office with certification of appointment by a proper official of the court.
Any other person shall provide a statement describing his or her relationship to the claimant, the extent to which he or she has care of the claimant, or his or her position as an officer of the institution of which the claimant is an inmate. The Office may, at any time, require additional evidence to establish the authority of any such person.