I am researching the Cashwell family of Amherst County VA. I know that John and Mary (Smith) Cashwell were both free people of color in Amherst County, VA in 1850. I am not sure how they became free. If anyone has any additional information on them please contact me?

Here is what I do know:
They had a descent amount of land in 1850. There children included Betsy, Carolina, John, Mary Jane, Virginia, Peter, William, Amelia, Catherine, John, Richard, and Samuel.

John Cashwell Sr is missing off Census records in 1860 although the rest of his family is available.

I also can't find records of his sons William, Peter and Richard in 1870 although they return in 1880.

Any additional information before 1850 and on Jon in 1860 or his sons in 1870 would be greatly appreciated.