I don't have any more on John; there are many papers in his estate file...mostly receipts and bills, settlement of his debts, and so on. He died in 1852 or was it '54. He and Hugh Holland d. about the same time. Unless both are buried in Dade Co., GA, I think they must be buried in unmarked graves likely somewhere on the homestead as I have been unable to find them in cemetery listings for DeKalb and death records, newspapers don't go back that far.
I believe John to be a brother to my Hugh Holland as he named his youngest son, Hugh Allison Holland. Allison was his wife's maiden name; they came to DeKalb, AL from Dade County, GA where they may have married. As I recall, John's widow Mary Holland md a Crow. It should be in my gedcom.
Both he and Hugh received adjoining land grants in DeKalb (in 1839, as I recall)...found info on a land website. Also, a William got a grant but don't think he ever moved to DeKalb; possibly, he was the father (or another relative) and might have died before he could claim it...speculation, not yet proved. John did name his first son, William F. I think they may have come from TN into GA, then AL.
Some of John's children--specifically William F. Holland-- moved to Indiana. Somewhere online, I found a very thorough website on William F.'s descendancy (up to 32 generations on at least one line). You might try a www search on William F. Holland.
My gedcom can be downloaded from this site if you so choose.