See notes for Nathaniel Pettit Sr. on some newspaper notices Nathaniel Jr. posted regarding his father's estate in 1809 and 1814.

Will of Nathaniel Pettit, dated 12 Nov 1845, probated 9 Feb 1846, mentions wife Rebecca, son Nathaniel, son Benjamin, son James, daughter Martha.

Sylvia Welch (see notes for Obediah Pettit) writes that Nathaniel Pettit Jr. married 1st Martha Clifford (no date given), who was the mother of all his children, and married 2nd Rebecca H. Atchison, on 23 June 1840, minister Robert Stewart. She lists as the children of Nathaniel & Martha: Nathaniel (no other data); Benjamin F. Pettit married Clara Barbee; Martha Pettit married David B. Henderson 28 Jan 1852; James O. Pettit. From census data, Nathaniel obviously had more children, but some of them may have died young.

1820 census of Fayette Co., Ky, lists on p. 95:
Nathaniel Pettit, 1 m < 10, 1 m 26-44, 1 f 10-15, 1 f 16-25. The teenage girl is probably Nathaniel's sister Rebecca. The family also had 10 slaves (3 m 14-25, 5 m 26-44, 1 f < 14, 1 f 14-25.) 9 persons total engaged in agriculture.

1830 census of Fayette Co., Ky, lists on p. 295:
Nathaniel Pettit, 1 m < 5, 1 m 5-9, 2 m 10-14, 1 1 m 40-49, 1 f < 5, 1 f 15-19, 1 f 30-39, 1 f 50-59 Since Nathaniel's mother died before 1814, the woman 50-59 is probably his wife's mother. It is not clear who the girl 15-19 would be, since there was no girl under 10 with the family in the 1820 census, nor with any other Fayette Co. Pettit family.

1840 census of Fayette Co., Ky, lists on p. 139:
Nathaniel Pettit, 1 m < 5, 1 m 10-14, 1 m 15-19, 1 m 20-29, 1 m 50-59, 1 f 5-9. The ages here suggest that Nathaniel's wife had died within the last 4 years. (Also note there is no f 10-14 listed, to correspond to the f < 5 from the 1830 census, who may have died.)

1850 census of Fayette Co., Ky, lists on p. 223, family #437:
Rebecca Pettit, 50, b. Ky; Catherine Denison, 80, b. Va; Martha Pettit, 17, b. Ky; Benj. Pettit, 12, b. Ky.