You mention a "family bible" Would you by chance have a copy of this bible?
I am fairly certain Edwin Dennis is Joseph Dennis' father yet am hoping to find some means of documentation before adding Edwin Dennis to my file. Marriage record, death record, obituary "family bible" etc.
I have an 1860 census image, Montgomery County VA, of James M. Rock 38 years old. On the census with James M. is Thomas Rock 80 years old and Sarah Rock 90 years old, a Mary Mitchell 22 years old and a James Mitchell 2 years old. I can email it to you if you're interested.
I have the 1870 census of Giles Co VA for Edwin Dennis 48 years old with Joseph Dennis on it.
I have the 1860 census of Roanoke Co VA for what looks like either Edwin / Edmund Dennis 37 years old. Has an Elizabeth Dennis 75 years old living with him.
I have an 1850 census of Roanoke Co VA of an Edward Dennis 25 years old.
You can email me direct if you want. Mention Dennis family and Genforum if you do so I'll know to look for it.