Ohio Rev. Code Ann. § 2123.06
Whenever it is necessary for any person other than an executor or administrator to determine who are or were the heirs at law of a deceased person, on the complaint of any interested party and proceedings similar to those set forth in sections 2123.01 to 2123.05 of the Revised Code, the probate court may make a determination of who are or were the heirs at law of the deceased person.