Go to the OAG. Ask the OAG to get you child support from the child's father. The OAG can file a suit affecting the parent-child relationship to determine paternity and to set child support. This will get done what you want to accomplish.
I am not intending this to be legal advice, because I don't know the particulars of your situation. Call me if you would like to discuss this or other isues.
The Attorney General's office can file a suit to establish him as the father. They can do a DNA test and it won't cost you anything.
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