William's place of birth as Bourbon Co. is from the birth records of his children Greenberry and Rena.

William's year of birth is unclear. Unless I have misidentified two William Jones, he was listed as 24 in 1850, when he and his two oldest children James (3) and Sarah (1) were living with his parents (see their Notes). He was also listed as 45 in 1870. And the 1830 and 1840 readings for James W. Jones Sr family are consistent with having a son born ca 1826, but not one born ca 1830. These 4 censuses thus suggest a birthdate of 1825-1826. However, the 1860 census lists him as 30, and the 1880 census lists him as 50, which would imply a birthdate ca 1830. The 1870 and 1880 censuses, though, are very clearly the same family, so the most likely explanation is that William and Barbara did not know their ages or the year they were born. I am going by the 1826 date, because age reports tend to be more accurate the earlier in life they are taken.

Dates of birth and death are from her gravestone, which lists her as Barbry Jones.

In the 1900 census, Barbara is listed as a widow, age 71 with her son Isaac, and her birthdate is given as July 1828. (She was listed as 29 in 1860, 42 in 1870, and 50 in 1880.) I haven't found her in 1850, when William and their two oldest children were living with William's parents James Wm. Jones Sr. & Lucinda. There is no Barbara Jones listed with any Myers family. Maybe she simply got accidently left off the list?

In 1850, two households after the James Jones family is that of Samuel Myers (age 31) and Emily Cassity, suggesting a possible relationship between Samuel and Barbara. Also, in 1860, Barbara and William were living next door to the family of John Evans and Elizabeth Myers, suggesting a possible relationship between Barbara and Elizabeth.

Morgan Co. Marriage register, book 1, page 77, records marriage of William Jones & Barbary Myers on 7 May 1846.

Even though William and Barbara married in 1846, in 1850 William and their two children James and Sarah are listed in the household of William’s parents James & Lucinda Jones, without Barbara. I don’t know where she was in 1850.

1850 census of Morgan Co., KY, lists as family #251:
James Jones Sr., 50, KY; Lucinda, 49, VA; Mary, 27, OH; Sarah 25, KY; William, 24, KY; Lucinda, 20, KY; David, 18, KY; Nancy, 15, KY; Josiah, 12, KY; John, 9, KY; Emmy E., 6, KY; William, 86, VA; Sarah, 75, VA; James, 3, KY, Sarah, 1, KY.

1860 Rowan Co. census lists on p. 36, family #273:
William Jones, 30; Barbary, 29; James, 13; Sarah A., 12; Rebecca, 10; Mary, 8; Joseph, 6; Isaac, 4; Green B., 6/12; all born in KY.

1870 census of Bath Co., Ky, Mudlick precinct, enumerated 24 Aug, lists on p. 39 as family #282/284:
William Jones, 45; Barbara, 42; Joseph, 16; William, 13; Isaac, 11; Green, 9; Rena, 7; David, 5.

I don't know whether the child William was missed in 1860, or whether he is not the son of William and Barbara. Tentatively I will assume the former, because Donald L. Jones of Marion, IN said that his grandfather David M. Jones had brothers Green and William. (See notes for David M. Jones.) I'm also not sure which age to believe for Isaac. He said in 1900 that he was born in May 1856, which would be consistent with age 4 in 1860, but that makes it hard to fit in William, so the "4" in 1860 may be a misreading of a "1". Or it could be that it was meant to be something like “William 4, Isaac 2”, and the enumerator left out a line. Anyway, the family is obviously not great at keeping track of ages, so I wouldn't consider what Isaac said in 1900 to be solid proof of his birthdate.

1880 census of Rowan Co., Ky, Pearce precinct, lists as family #199:
William Jones, 50, laborer; Barbra, 50; Rena, 18; David, 14.

The ages for William and Barbara are probably both wrong. Note also that Rena and David are only 2 years apart in the 1870 census, but 4 years apart in this one.