Nicholas is listed with his parents in the 1850 Census of Scioto, OH. age 7.

According to the 1870 Census:
The children of Abner and Jane (Gasaway) Howe are living with Nicholas and Mary. They are Aunt and Uncle on their Mother, Jane's, side.
Nicholas, age 20, born OH works on farm.
Nancy age 18 born OH
Thomas age 9, born IL [Age doesn't fit at all.]
Brother James is living with James Denson.

James Denson Gassaway served as the Administrator for, brother-in-law, Abner Howe's estate. It appears that Nicholas and his wife, Mary, shared in the responsibility for the Howe children, as well.

I can’t be sure this is the correct marriage record:
GASAWAY, NICHOLAS B m. POE, MARY E, CHRISTIAN Co. 05/24/1863 00A/0174 00001362
First child born in 1865.