White Family of Northampton County NC

John and Olive (as Olivia) appear in Northampton Co. NC in 1880 with the children listed below. I can't find John for sure in the earlier census years, nor can I find a marriage record. I found Olive's maiden name from their children's death certificates and then found her as a child living with her parents in 1850.

Could he be the John White age 15 living in Northampton Co. with Joshua and Mary Coggin in 1850, and/or the John White age 23, a farm laborer in 1860?

And was he the John White who enlisted in the Confederate Army on 15 Jul 1862, and served in Company E of the NC 56th Infantry?

Children of John White and Olive Edwards
Sarah White (ca. 1863-?)
James W. White (ca. 1866-?) m. Alberta Lowe
Rosa L. White (1868-1932)
Joseph L. White (ca. 1872-1925)
Edward Fisher White (1874-1945) m. Bettie Mae Williams,
   d/o James Richard Williams and Cordelia Ann Gums

The 1910 census says James married three times. Who were the other wives?

Sources