The reason I asked about the time and location is that there were two captains in the Missouri State Guard named Frank Davis, but they were from central Missouri and would not be the man you are looking to identify.

I looked at the 1860 census for Dunklin County and found only one man named Hawkins, a "D. Hawkins," a 24 year old clerk in Freeborn Township, which includes Clarkton. There are several men named Davis that could be the man in question: William (age 42); Francis M. (18); William (21); Henry (21); and Uriah (31). I realize that his information does not help much, but offer it for whatever it is worth.