The birth and death information comes from the research done on this family by Virginia Easley DeMarce (see the extensive notes in her tree posted on RootsWeb WorldConnect).  A photo taken by Robin Black of their grave stone in the Liberty Primitive Baptist Church cemetery just west of the school in Ashland, Missouri is available here.  John first appears as a son in the Abraham Black household in Fauquier County, Virginia by way of the Personal Property Tax (PPT) rolls.  The following excerpt begins with 1788:

John first appears in the Fauquier PPT lists 24 April 1788, which means he is at least 17 years of age at that point.  This places his birth date prior to 24 April 1771, but after 24 April 1770, if he was exactly 17 in 1788.  Likewise, his first appearance as a pole (21 years or older) on 24 April 1792 places his birth date prior to 24 April 1771, but after 24 April 1770.  The fact that he does not appear in 1791 says he could have been 21 at that time and just been missed by the tax assessor, as people were missed by the census taker.  Should this be the case then his birth date range takes in the birth date identified above.

One age item to note is that Peter begins to show in this household in 1790, placing him at least 17 years of age.  In 1793 he is enumerated in his own household in Greenbrier, placing him at 21 years of age.  Working backwards, that would mean he was actually 18 in 1790.  Did the same thing happen with John?  Was he not enumerated in Fauquier until he was 18?  Again, should this be the case, his birth date range takes in the birth date identified above.

An item of note in the PPT entries is the appearance of James Davison in 1799 and presumably close to John Black and family.  This is presumed to be John's father-in-law, father of Rebecca Davidson.  This was the only entry found for James in the PPT listings from 1782 through 1809 where he is clearly identified as Davison/Davidson.  Many other years contain a James Davis, who may very well be the same individual.  This excerpt also emphasizes the earlier statements about Abraham and Peter disappearing from the Fauquier scene after 1792.  And lastly, 1804 is the last year for which John Black has an entry in the Fauquier County PPT lists.  It is presumed that sometime shortly after this time John and his family migrated to Scott County, Kentucky where he appears on page 156 of the 1810 census.  Perhaps the migration took place in the early part of 1805, since daughter Martha was born in Fauquier County, and daughter Sally was born in Kentucky.

John Black appears in a couple of other Fauquier documents with association to the Abraham Black family.  The above PPT rolls show the association to be familial.  One is the Fauquier County lease document discussed with regard to Abraham.  In that document Peter, Adam and Jacob are identified as brothers, with John as a witness.  Assuming Abraham's sons are the parties of the one part to the lease, then John is also a brother as well as witness.  Additionally, Abraham gives his consent on 23 August 1791 for his daughter Mary to marry Conrad Dearing and John Black was surety.  Thus John is Mary's brother.

Notice that the first offspring of John and Rebecca bear their grandparents given names.  Isabella is thought to be the first name of James Davidson's wife.  James has the name of his maternal grandfather, while the next two children have the names of their paternal grandparents.

The children of John Black and Rebecca Davidson, as documented by Virginia Easley DeMarce, are:

1. Isabella Black, b. 4 March 1793, Fauquier County, Virginia; d. Abt. 1835, Callaway County, Missouri
2. James Davidson Black, b. 25 June 1794, Fauquier County, Virginia; d. 30 May 1871, Scott County, Kentucky
3. Abraham R. Black, b. 30 April 1797, Fauquier County, Virginia; d. (unknown), Howard County, Missouri
4. Elizabeth Black, b. 7 September 1799, Fauquier County, Virginia; d. 16 April 1866, Boone County, Missouri
5. Nancy L. Black, b. 27 April 1801, Fauquier County, Virginia; d. (unknown), Kentucky
6. Reuben Davidson Black, b. 20 February 1803, Fauquier County, Virginia; d. 28 September 1895, Daviess County, Missouri
7. Martha Withers Black, b. 13 January 1805, Fauquier County, Virginia; d. 24 March 1890, Boone County, Missouri
8. Sally G. Black, b. 17 February 1807, Kentucky; d. (unknown)
9. Eliza Black, b. 17 August 1809, Kentucky; d. 9 February 1879, Boone County, Missouri
10. Mary Black, b. 26 January 1811, Kentucky; d. 26 January 1811, Kentucky
11. John Madison Black, b. 18 August 1812, Scott County, Kentucky; d. 26 January 1851, Weaverville, Trinity County, California