My husband just found out he had a baby and she is adopted now... advise please.

Thank you for approving my membership here... I am in need of advice. I will try to make this as brief as possible. :) 7.5 years ago, my husband had an affair with a married woman. A few months later, she told him that she was pregnant and that it was his baby. My husband questioned the paternity of this child due to a number of circumstances, but mainly because she told him it was his, and everyone else it was her husbands. When he told her he wanted to do the right thing by her and take care of the baby, but she needed to quit playing games and fess up to whom the baby belonged, she told him the baby was in fact NOT his, and that she was fine to handle it herself. After going rounds with her for a while, he finally gave up on the games and left it alone. She, at that point, insisted that it was not his baby. Fast forward to a few weeks ago. My husband was thinking a lot about this situation as of late, and decided to look up the baby mama on Facebook. There staring back at him was a little girl that looked just like our son. He did not tell me about this find for a week or so, and then fretted about it for another week, before deciding he wanted to contact the baby mama and find out for sure if this baby is his, and do the right thing by her. We are aware that he probably should have pursued this a little more aggressively at the time of the pregnancy, but he was 20 years old, and not at all sure what to do. He sent her a message on FB, and she replied INSTANTLY asking when she could phone him. She phoned him last night and told him that the baby was adopted by her step-dad. We are 99% certain that her ex-husband was the person listed on the birth certificate, and that is why no contact was made with us regarding this matter (we are very easy people to find). ON THE FLIP SIDE OF THIS... Ironically, I have a daughter that my husband took on as his own at 3.5, and her father was not at all in the picture. My husband at the time was in the military and a future PCS was requiring me to do something about the rights of her biological father, as we were looking at leaving the country. I did not think it would be an issue at all, being that my daughter was 6 and he had never had anything to do with her, so I had a lawyer draw up paperwork and contact him. At that point, my ex decided that he would like to be a part of my daughter's life, and threw my life upside down. It was a very dark time for me, and I have acute awareness of how this mama is feeling right now. My daughter is 11 now and knows who her "daddy" is, but still enjoys and learns a lot from the time she spends with her father. If you were to ask me if I could go back and make a different decision, what it would be, I would honestly have no answer for you, as I have strong sentiments both ways. WE DO NOT want to destroy lives. My heart of hearts would love to think of it as adding to their lives, but I know that isnt realistic. Shes a beautiful little girl, and appears to have a wonderful "daddy", and we are very, VERY aware of how real that role is, to all parties involved. That being said, my husband would like her to know him, and know her siblings... but we dont know a) if it would be best to just leave her alone or b) if we even have any actual recourse. Thanks for listening and providing your feedback. Sincerely, Amy