Martha was born about 1938. She was the daughter of Erwin Davis and Florie Austin. Martha was a fourth cousin of Loretta Lynn and Crystal Gayle.
"Kentucky, Vital Record Indexes, 1911-1999," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:QKHG-DYD2 : 11 February 2018), Martha J Davis, 1937; citing Birth, Pike, Kentucky, United States, Kentucky Department for Libraries and Archives, Frankfort.
"United States Census, 1940," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:K7YL-T8B : 28 July 2019), Martha J Davis in household of Irvin Davis, McVeigh, Magisterial District 6, Pike, Kentucky, United States; citing enumeration district (ED) 98-25, sheet 7B, line 79, family 114, Sixteenth Census of the United States, 1940, NARA digital publication T627. Records of the Bureau of the Census, 1790 - 2007, RG 29. Washington, D.C.: National Archives and Records Administration, 2012, roll 1351.