"United States Census, 1900," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MM81-H5W : accessed 30 September 2017), Mary J Tannehill in household of Victor Tannehill, Jackson Township, Highland, Ohio, United States; citing enumeration district (ED) 112, sheet 9B, family 204, NARA microfilm publication T623 (Washington, D.C.: National Archives and Records Administration, 1972.); FHL microfilm 1,241,286.
"United States Census, 1870," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:M622-5VJ : 12 April 2016), Mary J Tannahill in household of Victor Tannahill, Ohio, United States; citing p. 18, family 130, NARA microfilm publication M593 (Washington D.C.: National Archives and Records Administration, n.d.); FHL microfilm 552,721.
West-6873 and West-10880 appear to represent the same person because: same dates. sources attributed to West-6873 appear to be relevant to West-10880 also.