Our earliest-known ancestor can be found on the Milacek line. He is Jan Taborsky, the father-in-law of Martin Milacek. Jan was probably born before 1680. Here's how we reached that conclusion: the Bohemian custom was that 24 was the age of majority, and most young people did not marry until they were 24 (but permission could be given by the fathers for younger people to marry). So if Katerina Taborsky was 24 in 1728 when she married, she was born in 1704. If her father was born 24 years before that, then he would have been born in 1680. We therefore estimate that he was born 1680 or earlier.