Although I don't have any Yunker's in MN or SD, I did find it rather unusual that you have a Yunker married to a Leu. I have John Yunker, married to Rosetta Leu. They came to the US in 1882, to LaGrange Co, IN. Don't know much about the Leu side. They came from Switzerland rather than Germany too. Probably not connection . . . but interesting all the same.