-651pair his recovery or would increase his mental debility, the inability or harmful effect shall be evidenced by the affidavit of a licensed physician or surgeon, or other licensed medical practitioner, unless the alleged incompetent person is a patient at a hospital in which case the affidavit shall be by the medical director or medical superintendent or acting medical director or medical superintendent of the hospital. (f) Affidavits provided by this section are prima facie evidence of the facts contained therein. § 2923. Appointment of guardian after hearing; preferences (a) After hearing and examination upon the petition, if it appears to the court that the person in question is incapable of taking care of himself and managing his property, the court shall appoint a guardian of his person or estate, or both, with the powers and duties specified in this Part. (b) I n awarding letters of guardianship of the person or estate, or both, of an incompetent person, the court shall appoint as guardian such person as may have been designated by will or deed pursuant to section 2804 of this title unless good cause to the contrary is shown. § 2924. Public administrator as guardian of estates of incompetent persons (a) The district court may appoint the public administrator guardian of the estate of an incompetent person. (b) The public administrator shall comply with all the provisions of this Part with respect to the guardianship of estates of incompetent persons by other persons, except that: (1) his official bond and oath shall satisfy the requirements with respect to a guardian's bond and oath; and (2) when notice is required to be given, the notice may, in the court's discretion, be waived or given by posting. § 2925. Restoration to capacity (a) A person who has been declared incompetent, or his guardian, or a relative within the third degree, or a friend, may petition the division of the district court in which he was declared incompetent, to have the fact of his restoration to capacity j udicially determined. The petition shall be verified, and shall state that the person is then competent. (b) Upon receiving the petition, the court shall appoint a day for a hearing before the court. If the petitioner requests it, the court shall order an investigation before a jury, which shall be summoned and impaneled in the same manner as juries in civil actions. The court shall cause notice of the trial to be given to the guardian of the person so declared incompetent, if there is a guardian, and to the person's spouse, if any, and to his or her father or mother, if living in the Canal Zone. (c) On the trialj the guardian or relative of the person so declared incompetent, and, m the discretion of the court, any other person, may contest the right to the relief demanded. Witnesses may be required to appear and testify, as in civil cases, and may be called and examined by the court on its own motion. (d) If it is found that the person is of sound mind, and capable of taking care of himself and his property, his restoration to capacity shall oe adjudged, and the guaraianship, if he is not a minor, shall cease.