I have in my notes that Simon Yunker Sr. was born in Germany. His wife was Anna.He came to the U.S. in the Dorothea 14 Oct 1787.Beleive he had six sons and two daughters but only have the names of three sons. His first is beleived to be Simon born abt 1780 in Germany. His wife was Nina. It is possible that Simon and Nina was married in PA.I heard where German immigrants would change the spelling of their names to be more like English.Simon and Nina moved to Orange Co. New York where most of their children were born includingHenry. They then moved on to Coshocton Co. Ohio where Simon and Nana died.I do have some information on Henry Younker and his family.It seems that you have about the same information that I have but I would like compare notes.