Are you going to meet them?
Not knowing my father I'm always worried that something like this will happen.
As for skeletons jumping out of closets. In grade 8 I was having super with my mom and grandma and they were talking about when my mom was 1...anyways long story short I found out that my grandpa isn't the blood father of my mom, so no blood relation to me, and that my grandparents didn't get married till till my mom was 2. I learn't all this in the course of about 20 seconds and what's worse is that they both assumed for some reason that I already knew.
Also one xmas my mom got a flower basket and when I read the name turned out it was my father. When I asked my mom about it, it turnes out he sent them to my aunts to because apparently my aunts and him still talk. That was weird.