Sec. 169. (a) "Responsible party", for purposes of IC 12-24-6, IC 12-24-13, IC 12-24-14, and IC 12-24-15 means any of the following:
(1) The patient.
(2) The parents of the patient if the patient is not more than eighteen (18) years of age.
(3) The spouse of the patient.
(4) The estate of the patient.
(5) A legal guardian of the patient in the guardian's representative capacity.
(6) A trustee of the patient if the trust authorizes payment for the care, treatment, maintenance, or support of the patient.
(b) The term does not include the children of the patient.