This is a matter that you almost certainly need the assistance of an attorney. It is possible to terminate a parent's rights involuntarily for the purpose of stepparent adoption, but there is a high burden on the party seeking to do so.
Legal disclaimer: this response is not intended to create any attorney-client relationship and is based on the limited facts given and should not be relied on as legal advice. It is recommended that you consult with an attorney before taking any action based on the foregoing statements.
You need to consult with a local attorney that handles adoptions. You are going to need to file a step-parent adoption and at the same time seek to terminate the father's parental rights.
Perhaps you can eventually get the father to consent to the stepparent adoption -- it sounds like he may be inclined to do so if he sees that his obligation to pay child support will terminate. You can even stipulate that any past due child support arrears be waived if he consents to your husband adopting the child.
Bottom line, call an experienced attorney to begin the process.
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It is very difficult to terminate someone's parental rights. They have to essentially be a danger to their children in order for you to prevail. Perhaps if you were to have a conversation with the father regarding your concerns, this might bring about some better behavior on the father's behalf?
Bill Rosenfelt 407-462-8787 (Orlando/Longwood/Central Florida)
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