Your ancestor, William Garner, was still alive in 1900 and appears on the 1900 Federal Census of Montgomery County, Mississippi. In the index at Ancestry.com his name is spelled "Gamer", but if you look closely at the original record his name is correctly spelled "Garner".

Wm W Gamer (Garner)--age 70--born December 1829 in Mississippi
M Catherine Gamer--age 71--born June 1828 in North Carolina
Edgar Sanders--age 14--grandson
Hatchie Sanders--age 16--grandson
Wm T Roseman--age 1/12--grand nephew

Source Citation: Year: 1900; Census Place: Poplar Creek, Montgomery, Mississippi; Roll: T623_820 Page: 9A; Enumeration District: 83.

Source Information: Ancestry.com. 1900 United States Federal Census [database on-line]. Provo, UT, USA: The Generations Network, Inc., 2004.

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