Don't even know how to feel

So 9 months after my father's death, I find out there are four other women that have most likely had his children and I have absolutely no way to get in contact with them. I feel terrible, I don't even know their names. How am I even supposed to find them? I have so many things running through my mind and can't make any sense of it. Sorry for not making any sense I just needed to vent 😧