Where a petition is filed for the appointment of a guardian for a mentally incompetent ward, a certificate of the administrator, or the administrator's duly authorized representative, that the person has been rated incompetent by the veterans administration on examination in accordance with the laws and regulations governing the veterans administration and that the appointment of a guardian is a condition precedent to the payment of any moneys due the ward by the veterans administration, shall be prima facie evidence of the necessity for the appointment.