The court shall hold a hearing on the merits of the petition no sooner than forty-five days after the date of filing but within sixty days after the date of its filing. The petitioner shall notify by certified mail the petitioner's parent or legal guardian or the petitioner’s nearest known relative residing within the state, whichever is given notice under section 43-4806, if any, and the petitioner’s legal custodian, if any, of the time, date, and place of the hearing at least thirty days prior to the hearing date. Proof of such notice shall be filed prior to the hearing on the petition. For good cause shown, the court may continue the initial emancipation hearing.