I think Kost may have been a son of Moses. As you can tell this is a fairly old post so I have been able to find out a lot since then. If you like send me an email to firstname.lastname@example.org
and I can add you to the tree I have here. There are many pictures and stories, many I am sure you haven't seen before. I am not a blood relation, but my father bought the old Screpnek homestead back in 1979.