Hire a lawyer to help with development and presentation of evidence in the modification.
This answer DOES NOT establish an attorney-client relationship. This answer is based on the limited information provided and is not intended to be conclusive advice. There are likely other factors that might influence or change the advice after a more lengthy consultation.
Unless the court order already requires supervised visitation then you need to pursue modification of the order to require supervised visitation. It also sounds like you need some help enforcing the child support provision. Talk to a family law attorney in your area.
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