My husbands sons mother is currently in prison for trafficking and manufacturing narcotics. She also has to face several harassment charges, DUI's and one child endangerment charge when she gets out of prison in PA, here in SC. She also has had another child (4 months old) die. Granted it was ruled as accidental, it is still highly suspicious. We currently have full custody of his son, however his mother is threatening to gain custody of him again when she gets out of prison. We have heard that we could get her rights terminated so that she can no longer try to gain custody of him. Does anyone know how we could do this. She is crazy and we are worried that the court system will not always be on our side or on the child's side.

Yes you may try, and yes the criminal offenses and long prison stay can be reasons to ask for loss of rights.

At best of course you do want a full custody both legal and phsycial in place with her no visits or supervised only.

But you have a good chance of winning, but you will need the best attorney you can afford