My great-grandfather Atherton (first name unknown) was a photographer. I have studio photos with his imprinted logo from Charles City Iowa, Cedar Falls Iowa & Big Rapids Michigan. He was probably born around 1860. It is my understanding that the mystery surrounding his identity is because he had more than one family at the same time.My great-grandmother, Mary Frances Atherton (who died in 1940), left her husband because of this and moved with her only son, Harold, to Ontario, Canada. Does anyone know who my great-grandfather is?