Ohio Rev. Code § 2111.46
When a guardian has been appointed for a minor before the minor is over fourteen years of age, the guardian's power shall continue until the ward arrives at the age of majority, unless removed for good cause or unless the ward selects another suitable guardian. After the selection is made and approved by the probate court and the person selected is appointed and qualified, the powers of the former guardian shall cease. The former guardian's final account as guardian shall then be filed and settled in court.
Upon the termination of a guardianship of the person, estate, or both of a minor before the minor reaches eighteen years of age, if a successor guardian is not appointed and if the court finds that the minor is without proper care, the court shall certify a copy of its finding together with as much of the record and any further information that the court considers necessary, or as the juvenile court may request, to the juvenile court for further proceedings. Upon that certification, the juvenile court shall have exclusive jurisdiction respecting the minor.
R.C. § 2111.46