Suggest you look at naming patterns.
Dan named one of his sons Doc or Dock. There is an older Abe Adams, born VA (1870 census) and wife Tempe that also have a son Dock.

From online sources at ancestry - it shows that there are early records of marriages for Monroe county available. Would send for as many as possible - to begin to make connections.

Unfortunately - there were no large Adams slaveholdings in Monroe county. Perhaps the surname was carried over from a previous owner.

There were very large Cox holdings.

Your research pre-1865 will be mostly with the records of slaveholding families.

I don't know what is available in terms of co-habitation records and labor contracts for Monroe County - am not a MS researcher. You will need someone knowlegeable about MS research and that county to guide you to the data available.

Dan, 36 and Mary 22 in 1870 - are closer in age than listed in later years, and the oldest child listed is 5 - which would make her 17 at the time of his birth. It might also indicate that Dan and Mary hooked up around emancipation time - would look for a marriage record.

Since the 1870 records show a housing pattern with quite a few Adams in close proximity - I'd start with those families. Have you contacted the geneological/historical society for that area?

Death records often mention parents - I'd see what is available. Sometimes local (white) newspapers have articles about blacks if they die very old - contact the library .

Denise