The Indiana county of Dubois is not that far from northern KY. What part of KY did your Ambs live in and when?
My first PROBABLE Ambs was Xavier Francis Ambs b ca 1792? and died aft 1877 in PA. His son Francis X Ambs b 1815 in PA and died 1876 Dubois Co., IN.
Xavier Francis Ambs (b ca 1792?) is supposed to have had the following children: Nicholas b 1815 or 1822, George b 1822, Joseph b 1834, Lewis 1828, Mary 1840, and Frank G b 1851 -- although I have serious doubts about some of this history. Anyway, keep this family in mind as you search for your German family.
Best wishes. Sue