Pro Bono means for the public good. A private custody dispute most likely does not qualify.
You might contact the legal aid section of your local Bar Association or courthouse to see if affordable legal services are something you qualify to obtain.
Meanwhile, you are right to seek legal counsel. The concerns about the best interests of your daughter are too important for you to try and defend yourself Pro Se.
NJ does not offer such a legal service. You should contact your local bar association for a lawyers' referral program because such attorneys generally discount their rates.
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