I'd like to add to what was posted. You can request a psychiatric evaluation of the other parent (which you may be required to pay for, and you'll likely be required to take one yourself), and you can also request a Guardian Ad Litem be appointed who will act on what is in the best interest of the children. To do all this, you'd better hire a family law lawyer and get a plan of action in place. Trying to do this pro se without an attorney is a recipe for failure.
Good luck to you.
God bless. Best of luck to you.
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