In my family tree info I have Jemima husband's name as George. In the 1880 census the family is listed as: George S. Mount, age 28 (notice the incorrect spelling) Jemima Mount, age 26 Dona F. Mount, age 2 Homer W. Mount, age 2 Congress Township, Morrow Co., OH
My information lists Homer and Dolly as twins with siblings Maude, Laura and Mae.
I do not have any information of parents or siblings for either George Mountz or John Ephram Mountz; sorry.
Are you Robert & Carol's daughter? I grew up on a farm just north of your grandparents Ralph and Nellie. I also remember your great-grandmother Carrie.