I think i'm the father
The title isn't the biggest issue. Basically, I'm 19, my half sister is 21. About 4 years ago, we both started to get closer to each other (We have only known about the others existence for 6 years). And the thing is we never really saw each other as our sibling. After she had her stuff moved into our house (About a year and a half, after meeting her), her bedroom was next door to mine. At night, we kept sneaking into each others rooms (nothing sexual, not at first) and messing about. One night she came into my room wearing a t-shirt and her knickers, and climbed into bed with me. During the night there was the occasional kiss and wandering of hands. We had nights like this for a few months, then one night it went a bit further. We eventually started having sex. Now I love her, so I don't care what you have to say about that part. She started going out with a guy about 2 years ago, but we still continued having sex. And a year and a half ago she got pregnant. Thing is she had just dumped her boyfriend a week or so before she announced her pregnancy. (We haven't heard from him since). My theory is that my little niece is also my baby girl, and she had to break up with her boyfriend because they hadn't slept together. I have been wanting to ask her for months, but I couldn't. How do I go about this situation???