I think we are gaining on this. Now I have 13 brothers, but Doctor Matthew Bone was probably too young for service. ("Doctor" was really his name. I doubt that he was a physician.) That leads to the question whether DM and Doc are the same. It seems unlikely.

Here are some more possibilities:

Henry T./Y. Bone, MAJ/LTC 11 Tx Cav
HF Bone, Hospital Steward CSA
Leonidas J Bone, 6th Tx Cav, Co C (I hadprematurely ruled him out)
Thomas J Bone, 1 Batt'n Texas Sharp Shooters Co C
Caxy C Bone (what kind of name is that? spelling error?)

Do you have any info on these guys?