Ohio Rev. Code § 5301.22
As used in this section, "incompetent person" means a person who is so mentally impaired, as a result of a mental or physical illness or disability, as a result of an intellectual disability, or as a result of chronic substance abuse, that the person is incapable of taking proper care of the person's self or property or fails to provide for the person's family or other persons for whom the person is charged by law to provide.
No agreement described in section 5301.21 of the Revised Code shall be executed by a minor or incompetent person, but it may be executed and delivered for record, on such a person's behalf, by the person's guardian. When executed, acknowledged, delivered for record, and recorded, such agreement shall be as effectual against such minor or incompetent person, as if the person had been under no disability, and had performed such acts personally. An owner, not under any of such disabilities, may perform all such acts by an attorney in fact. The power of such attorney must be in writing and first recorded in the county recorder's office.
R.C. § 5301.22