This is too delicate to be casual about. You are asking for trouble if you do not consult a family court attorney and follow legal advice, which will depend on the facts, including available third party resources to protect the child while you work through the paper. There may be resources specific to homeless teens.
DISCLAIMER: I am not your attorney and readers employ any information provided herein at their own risk. Any comment is for general educational purposes only, and is based only on the limited facts provided, which may or may not be true. It is not legal advice upon which you may rely, as the commenter has not interviewed witnesses or examined any evidence, and has not researched the applicable law. Available defenses may prevent the success of any claim. Competent legal advice should always be obtained from a lawyer licensed in your jurisdiction before taking any legal action or filing suit.