Lawrence County Alabama was created Feb 6, 1818 from lands ceeded from the Cherokee and Chickasaw Cession of 1816 so you'll find records in Lawrence County Alabama.
I didn't find anything for the family members after the 1850 Lawrence Co. AL Census. I assume that Freeman and Sarah died there. The Alabama Archives has Probate Court Minutes 1850-1941 and deed records 1819-1932.
The Lawrence County Archives, www.lawrencecoarchives.com/
also records that should help you prove when and where they died. They have cemetery records too.
You might find additional records at the Tennessee Valley Genealogical Society, www.tvgs.org/
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