You should file for custody in Family Court in Ohio and haave her served. Generally a Marshal in another state is given the papers for filing or you can hire a proces server in the state she is in as well. They are easy to find online. You need to do this because Ohio it the "home state" of the children as of now. If, however, they are gone for more than 6 months, Ohio courts lose the ability to decide cases involving them (called Jurisdiction). Good luck.
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