My husband has sole custody of his son and has had it since his son was born. The mother is not in the child life. Can I legally adopt him? What do I have to do to ensure that this happens?

You have to get the child's mother to relinquish rights before you can adopt.

Custody has NOTHING to do with parental rights--it just says who the child lives with.

You need to get a lawyer to walk you through this process to make sure that it is done correctly.