question and advice?

Sorry if this post is long! I had a daughter a little over 15 years ago that I placed for adoption whom I have never seen. She contacted me (actually her friend did at first) in April of this year. She (through her friend) asked numerous questions, etc. Eventually, she contacted me through text herself. We had a few conversations through text that went well. I asked her how she found out my name, etc. and she said that she went into her AP's safe one day to get something out and saw the adoption papers in there and looked through them to find out my name. She told me that she has always known that she was adopted, her parents never hid that from her. I asked her if they knew that she found out my name or if they knew she had made contact with me and she said no and that she didn't plan on telling them anytime soon. Since she is a minor, I told her that I didn't know if we should be having communication without her APs knowing. I then suggested to her to maybe tell them? She told me that she was too scared to tell them b/c she had asked her adoptive dad questions about me a few years ago and he told her to be quiet so that she wouldn't upset her mother. I told her that I didn't think it was right to communicate with her behind their backs and that from a legal and moral standpoint, I could not have any communication with her until and/or if she decided to tell her parents and that only she can make that decision. I also told her that I would respect whatever decision she made and that if she did not decide to tell them, I would wait as long as it took. Like I said, this was back in April of this year and it has been bugging me since then. I REALLY want to have some form of communication with her and it is killing me not to. I'm not sure if there are any legal issues with this because she is a minor or not, but I just keep trying to put myself in her AP's shoes. What do I do?????