Sorry! I misunderstood your question. I haven’t found a connection between Doc and Howell Adam Rayburn, but H.A. was a namesake of his uncle, Howell Adam Rayburn (circa 1793 SC), so it is possible that Doc got his name from the same person, but so far there is no concrete evidence to support this.

H.A.’s parents were Noah and Elizabeth (McSwine/McSwain), and Noah’s parents were Thomas and Elizabeth (Adam). As you know, Doc’s father was Hodge Rayburn, so the possibility exists that Thomas was also Hodge’s father, and that he and Noah might have been brothers. I have not been able to connect them as kin, and if I can’t prove it, I don’t use it. Just tossing out a point of departure.

I think the Hodge Rayburn buried in Cleburne Memorial Cemetery was Hodge Sr.’s son by his first wife Rosanna Hardin. This is a tough one to prove because Hodge Jr. was on his own by 1850 (first census to include all family members). As you mentioned, Hodge Jr. appears in the 1860 Census for Leon TWP, Leon County, TX, which put him in the area of recruitment (Captain Whaley was David Moreland Whaley, Captain of Company C, “Leon Hunters,” 5th TX INF, formed 11 Jul 1861 at Centreville, Leon County, TX). Note that there was a James Rayburn, born GA, in Hodge Jr’s household in 1860, and a James Rayburn, born GA, in Hodge Sr’s household in 1850 (note below). Ages do differ, which is not rare.

William B. Rayburn was Doc’s brother. Hodge’s children were James, b. GA, Mary C., b. GA or TN, William B, b. TN, Milton V., b. AL, Howell A., b. TN or AL, and Robert L., b. TX.

The following census shows William in his father’s household.

Hodge Rayburn Household, 1850 U.S. Census, Shelby County, Texas Population Schedule, Page 17A, Lines 12-19, Dwelling 224, Family 224, National Archives Micropublication M432, Roll 915

o Hodge Rayburn, 48, NC (the enumerator spelled it “Hodg”)
o Susan, 36, TN (Susan White – 3rd wife)
o James, 18, GA
o Mary C., 13, GA
o Wm., 11, TN (born 1839 – matches cemetery info)
o Howell A., 9, AL
o Milton, 7, AL
o Robert L., 1, TX

The following census shows William B. in his brother-in-law’s household.

Jas. Haley Household, 1860 U.S. Census, Johnson County (formed from Shelby County), Texas Population Schedule, Page 446, Lines 19-27, Dwelling 141, Family 142, National Archives Micropublication M653, Roll 1298.

o Jas. Haley, 32, LA
o Mary C. Haley, 23, TN (sister of Doc and William b.)
o Mary E. Haley, 5, TX
o Sarah J., 3, TX
o Susan, 1, TX
o Chas. M. Jackson, 23, farm labor, AL
o Wm. B. Rayburn, 21, farm labor, GA
o Milton V., 17, farm labor, GA
o Robert L., 10, TX