1900 census of Morgan Co., Ky, district 6, enumerated 26 June, lists on p. 22A as family #341/345:
Horseley, Watt A., 67, b. Oct 1832, Ky Va Va, farmer; Rebecca, wife, 36, b. Mar 1864, Ky Ky Ky, married 20 years, mother of 10 children, 6 living; Thomas, stepson, 18, b. July 1881; Nancy, dau, 15, b. July 1884; Peter, son, 10, b. Nov 1889; Peachy, dau, 6, b. May 1894; Minnie, dau, 2, b. Jun 1897; Delila, dau, 11/12, b. June 1899. All children born Ky Ky Ky.

The identification of Thomas as a stepson age 18 seems inconsistent with the 20 years married.

1910 census of Morgan Co., Ky, Panthers Branch precinct, undated, lists on p. 7B as family #103/104:
Hansley, Abecca M., 50, widowed; Tomie, son, 26, farmer; Nancy, dau, 24; Peter, son, 20; Peachie, dau, 14; Minnie, dau, 18; Dee, dau, 11; Pearlie, dau, 15; Willie, grandson, 3/12; Ben, son-in-law, 48, married, farmer; Brown, Tom, boarder, 23, single, farmer. All born Ky Ky Ky.

Note that the daughters are listed out of order. I do not know who Ben’s wife is; all of the daughters in the household are listed as single. Judging by the 1920 census, Willie is a son of Nancy, most likely born out of wedlock.

1920 census of Morgan Co., Ky, Panthers Branch precinct, enumerated 29 Jan, lists on p. 13A as family #234/239:
Horseley, Rebeca, 58, widowed, farmer; Henry, son-in-law, 50; Nancy, dau, 35; Willie, son, 10; Brown, Thomas, son-in-law, 33; Pearl, dau, 17; Leslie, son, 6/12; Cassity, Nancy J., mother, 85, widowed. All born Ky Ky Ky.

The relationship for Willie Horsley and for Leslie (aka Luster) Brown should be given as grandson, not son.