Let’s start with sources closer to her birth and work forward
I found this on familysearch.org a free site
: John A Thomas M 56 Virginia
: Nancy Thomas F 40 Tennessee
: William H D Thomas M 15 Tennessee
: Ema A Thomas F 13 Missouri
: John M Thomas M 7 Tennessee
"United States Census, 1870," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:M4F4-F3V : 12 April 2016), Ema A Thomas in household of John A Thomas, Missouri, United States; citing p. 18, family 119, NARA microfilm publication M593 (Washington D.C.: National Archives and Records Administration, n.d.); FHL microfilm 552,325.