You raise a number of issues.
For the purposes of terminating his parental rights, the statute says that after a year of non-support, his rights can be terminated. However, terminating a parent when there is not a step-parent ready to adopt can be tough for public policy reasons. (I am very familiar with the courts in Dallas county and can tell you that it is not impossible to terminate him, just not a slam dunk.)
However, what you CAN do is file a determination of parentage action on him and get him to start paying child support. That IS a slam dunk, if he's really the biological father.
You would need a lawyer to help you with this. If you can afford a private attorney, that is your best (fastest) route. If you can't afford a private attorney, consider these options:
1. The Office of the Attorney General will handle the case for you at no cost to you. It can take a long time, particularly if the dad evades service of process.
2. The Dallas Bar Association Volunteer Attorney Program (DVAP).
3. Legal Aid of Northwest Texas (LANWT).
The cost to you through any of those three agencies would be zero. DVAP and LANWT might not be able to take your case, though, but it can be worth a try if you meet their income guidelines.
A fourth alternative is to contact the Texas Legal Services Center (www.tlsc.org). They can refer you to an attorney who will work at a great discount. Typically the discount is from 50% to 70%. You would still have to pay filing fees and service of process fees.
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