Names and years of birth for Tobias' children are mostly from correspondence with Pauline Q. Seigo. I suspect that the years may really be derived from census records, and if so, are only approximate.

In 1870 Isabel is living with the family of her son Crockett, listed as age 57, see his notes.

In 1880 she is listed as age 73, widowed, with the family of her son Edward and his wife Anna.

1850 census of Floyd Co., Virginia, district 15, enumerated 4 Sep, lists as family #895:
Tobias Quesenbery, 41, farmer; Elizabeth, 38; Loyd, 17; Newell, 14; Alexander, 11; Crockett, 10; Milton, 8; Louisa, 4; Millan (m), 7/12. Tobias born in Floyd Co., all others in Carroll Co.

(Although I suspect that really only Louisa was born in Carroll Co. Hers is the only line that really says Carroll. All the children just have ditto marks, and the enumerator may have been thinking of the dittos as meaning Floyd Co., since they did for most families.)

According to Barb Reininger’s Floyd County Families web site, the male Millan should be a female Emaline, and is the same person as the daughter Evaline age 10 in 1860. There is no further data on either, though.

1860 census of Floyd Co., Virginia, Indian Valley township, enumerated 1 Aug, lists on p. 133 as family #965/901:
Tobias Quesenberry, 50, farmer; Isabell, 50; Alexander, 22; Crockett, 18; Milton, 15; Louisa, 13; Evaline, 10; Edward, 8. All born in Virginia.