She is often confused with her cousin, Rachel Norton, daughter of Ransom Norton as they were the same age.

1850 Kaufman Co., TX census
244 245
Aaron Norton, age 45, M, Farmer, b. New York
Polly A. ", age 43, F, b. Kentucky
Rachel ", age 21, F, b. Kentucky
Abigail ", age 16, F, b. Kentucky
William L. ", age 14, M, b. Kentucky
Margret A. ", age 12, F, b. Kentucky
Stephan M. ", age 10, M, b. Kentucky
Fredrick M. ", age 7, M, b. Kentucky
Jemiah (Jeremiah) B. ", age 5, M, b. Kentucky
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Home in 1860: Precinct 6, Hunt, Texas
Post Office: Caddo Villa
Robert E Thomas 20, TN
Rachel Thomas 23, KY (abt 1837)
Andrew J Bassham 6, TX

Rachel's age in this census is incorrect. She should have been about 31. In her father's will, Aaron Norton, she is listed as, my daughter, Rachel M. Thomas.