He told her we had moved away and he lost track of us. this was 40 years ago and she made no attempt to find us. He didn't tell me for several years and I was thankful that I didn't know because I would have been worried that she would show up on our doorstep one day. This was back in the day before open adoptions.
I have four adopted at birth children.
The baby is not yours until it is legally yours. It is not legally yours until all rights are signed off.