I have a lot of information on the Tuvell side and I have a little on the Bivens side. I am having some trouble connecting George Tuvell to Robert Tuvell . I am leaning to the fact that Robert (Tubble)Tuvell and George Tuvell are brothers. Since they are in the same area and close in age. I think that their father is the John Tubble that shows up in the 1840 census in pike county Ohio born in about 1781-1790. He had to have died before 1850. Tubble is the original name for the Tuvells. We have George in the 1850-1870 Census. I hope this helps.