This family is confusing. One might think from the censuses below that Nathaniel was married to a Nancy in 1860 and remarried sometime before 1870 to a Mary E., and remarried by 1880 to another Nancy. But Floyd Co. birth records list a son John G. Quesenberry born to Nathaniel and Mary E. Quesenberry on 1 March 1860, which is three months before the 1860 census was taken where he appears with a wife Nancy. I cannot find any other Nathaniel Quesenberry in either the censuses or in Quesenberry family genealogies. Nor can I find any John Quesenberry born ca 1860 in the 1860 or 1870 censuses. So unless Nathaniel was fathering sons by two different women in the spring of 1860, one of which sons (John G.) died in infancy, then John G. may be the same person as Addison F., and Nancy the same person as Mary E. But if so, it seems quite odd for Nancy to sometimes go by Mary E. when she had a younger sister named Mary. Maybe she was really named Nancy E. and some of the records got her name wrong.

1860 census of Carroll Co., Va, Dugspur P.O., enumerated 16 June, p. 10, lists as family #60:
Quisenbery, Nathaniel, 25; Nancy, 25; Crockett, 2; Addison F., 1/12.
(Nancy’s parents are in the preceding household at #59.)

1870 census of Floyd Co., Virginia, Indian Valley precinct, enumerated 31 Aug, lists on p. 40 as family #275/259:
Quesenberry, Nath’l, 37; Mary E., 36; Crockett, 12; Addison F., 10; Damia A., 8; Mary R., 5; Andrew J., 3. All born in Virginia.

1880 census of Floyd Co., Virginia, Indian Valley district, enumerated 5 June, lists on p. 14 as family #120/121:
Quesenberry, Nat, 44, farmer; Nancy, 48, wife; Crockett, 19, son; Adison, 18, son; Didama, 16, dau; Mary, 14, dau; Andrew J., 11, son; Albert C., 9, son; David E., 6, son. All born Va/Va/Va.

If Nancy and Mary E. are different people, then I do not know for sure which mother each child belongs to.