You know SD, I know it's a HUGE transition for you coming here to live with me and your Dad. And I appreciate how hard the adjustment has been for you. I want you to know I love your Dad very much, and I love you kids very much and I want to help anyway I can.
I want you to know you can talk to me about anything. There IS no issue we can't work out together, k?
I think you're a great kid and I want you to have a great future, so if you'd like, I can make a drs appointment for you. We can go together, you can talk to the doc about birth control and such if you like. Or you can talk to me, ok? You can even tell me about bfs, right? I'm a girl too, afterall, I've been there. And boys can be pretty stupid (eye roll, and instant bond).
(Patting her on the shoulder and getting up) So really, ANYTHING at all you want to talk about,it's cool, right?
(Follow up from time to time, but don't hound her)
Least that's what I'D try.
:)