I met my husband 8 years ago and he was going through a divorce in which him and his now ex wife shared a daughter. She was 2 at the time. The mother(even though they were divorcing) still lived in the same home. I will say it was about 2mths into me and my husband getting serious she moved out and across the state from where we lived. From this point we never heard from her again. My step-daughter(which I claim as my own) knows of her bio-mother because I have discussed her with my step daughter. My step daughter is now 11 and I have raised her as my own since the day her bio mother disappeared. My step-daughter told me recently that she wants me on her birth certificate and would not like to meet her Bio mother. What do you think we would have to go through for me to adopt her since the bio mother basically abandoned her and has had no contact with her since? Since her father and I married she now has 2 brothers and a sister. I would love to adopt her because she has become one of my own and I have been her parent all these years. What do we do and is it possible her mothers rights could be terminated since she has left with no contact for so many years?

Yes, this is all possible. But you need to hire an attorney to go through this. You have to get the bio mother's consent or at least make a good faith effort to do so. If you contact the mother and she refuses to consent, the abandonment may be enough to get her rights terminated as long as you stand ready to adopt. But this all has to be done completely within local laws. So speak to a Family Law attorney who will prepare all the paperwork and make sure all the Is are dotted and Ts crossed.