First, you need to back to court and have another DNA test done. If you have proof that she got in your husbands files to gather info on him, you need to talk that over with your lawyer. And, yes it could just be a money ting, she may have been doing fine all these years and now she needs help. If the child is really your husbands daughter, then he should be paying shild support. And if this girl is really your husbands daughter, you can't expect your daughter to just want to become BFF's with her, but you do need to explain to your daughter that this girl is her sister like it or not and try to help build a bridge you can all cross together to get to know her. For me, family is so important, you need to do what you can to find common ground. If/when you go back to court to have another DNA test done, that is also your chance to get time with the other daughter legally. The mother will then not tell you can't see her, she will have no chose. If this girls does get proved to be your husbands daughter, I would suggest all of you including the new daughter, seek councling to help you cope and learn to handle one another. Good luck.