[KatiesEd-dad]

That's a tough one but I would start bringing the subject of her bio father up gradually (age appropriate for sure). Kids are a lot smarter than we give them credit for most of the time. You might want to start with a few of the basic birds/bees facts. We actually started talking about this one day when we stumbled across one of those child birth shows on Discovery Channel. My daughter was a little over 2 y/o and was fascinated by the babies coming out of the womens tummies. So we started with - it takes a man and a woman to make a baby and the baby grows in the mommies tummy and just took it from there. I wouldn't wait a whole lot longer to get this going.