1880 Franklin Co. TX
Arron Brown, b. TX, 30, farmer
Margarrett, b. TX, 25
Willie, son, b. TX, 7
Lorry, dau, b. TX, 3
Generally you use the information closest to the actual date, e. g., Margaret born in TX. However I didn't find her in Texas either before her marriage.
No parents names were on their marriage license so there's no help there.
Margaret Catherine Netherlin Brown
Born: 25 Nov 1853, TN
Died: 19 Oct 1931, Franklin Co. TX
Buried: Cypress Cemetery, Cypress, Franklin, TX
Her death certificate is attached on FAG but there's no additional info on it that helps. She might have been an orphan.
I'd consider using a DNA test. There is a good article "Finding Your Birth Parents Using DNA", Family Tree Magazine, 12/17. You can do a Google search and read it for free. It's good info even though you don't know if she was adopted.
I'd also do a Google search about DNA and Native American content.
By the way, I'd also post this query on the Tennessee State and Texas, Franklin County Message Boards. I can't see where/when she lived in Powhatan Co., VA. Successful Searching!