I recently found out that when my father was 16, he got a young lady pregnant. Being as that my dad didn't marry my mom until he was in his 30's, the young woman in question is obviously not my mom. So if this baby is still alive, I have a half sister who is around 65 years old. I know very little at this point. My dad made his relatives who knew about this promise to not tell me until after my mom passed away. I'm really not sure if I should try to find my half sister or if I should leave it alone. If she is alive and happy and has no idea of her true identity, this is the type of information that could devastate a person. Although I am curious, I don't want to be responsible for causing pain to another person. I have so many questions and very few answers. If anyone has been in a similar situation, any advice is appreciated. Thank you.