R.K.
Here's the deal. If you make a big deal out of it, she'll make a big deal out of it. If you look like it's this Big Secret Confession like there's something wrong She WILL pick up on and carry it forever.
So before you talk to her you need to get right with yourself.
~You chose poorly the first time. Yep. Ok.
~You were given a miracle. Yes. Absolutely. Her.
~You chose wisely and now have a wonderful man who IS this little girl's Daddy! DNA mean a whole lot of nothing really.
~The male who got you pregnant wants to meet your daughter.
~He is somewhat decent because of the child support. Thousands of males do not. So, he's at least provided for her and has a bit of an "investment" (for lack of a better word)
That's it. Those are the facts. That's what you tell her. The END.
No emotional issue.
He's just the guy that got you pregnant before you met her DADDY. That's what you tell her. DADDY is the one with the realationship.
This person has to earn the right to be called a "real" anything and he's at a huge deficet.
This is only as big as you choose to make it.
Other advice I have for you is to contact a family attorney and see what possible rights you have and what he may have for you to formulate a plan if the state chooses to grand visitation.
Absolutely under no circumstance other than a firm court order to let her alone with this stranger. If he wants to meet her he meets THE FAMILY and interacts with THE FAMILY.
That my buck fifty on the subject. Hope it helps. :o)