Ohio Rev. Code § 2119.01
When a person owning property in this state has disappeared and has not been heard from, after diligent inquiry and for at least three months, under circumstances that afford reasonable ground to believe that the person is dead, cannot return, or refuses to return to the person's home, and the person's estate requires attention, supervision, and care, or is needed for the maintenance of the person's dependents, the probate court, on application of the spouse or of one of the next of kin, may appoint a trustee to take possession and charge of the property of the person, other than the property with respect to which the person has made provision by written instrument designating an agent or attorney in fact. The application shall be filed in the county in which the person last resided or if the person's last known residence was outside this state, the application may be filed in any county in which that property is situated.
R.C. § 2119.01