Ohio Rev. Code § 2127.14: Service of summons.

Service of summons, actual or constructive, in an action to sell the real property of a decedent or a ward shall be had as in other civil actions, but if any competent person in interest enters appearance or consents in writing to the sale, service on that person shall not be necessary. If all parties consent in writing to the sale, an order for the sale may issue forthwith.