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Just in case you don't have Thomas and Hannah are both on findagrave.. 12 children are listed.
Don't know if your are familar with familysearch,org...it is a free website..you just need to register to search.
You might be busy...looking for 12 children.....
Here is the 1870 Census https://www.familysearch.org/ark:/61903/1:1:M46P-J6J
Here is your family tree https://www.familysearch.org/tree/pedigree/landscape/KFYS-QWP
Dear Ms. Day,
Thank you for posting your request on History Hub!
We suggest that you contact the Library of Virginia and the Missouri State Archives to request a record search for Thomas Day. We also suggest that you review the FamilySearch research wiki for Virginia and Missouri Genealogy.
We hope this is helpful. Best of luck with your research!