The 1940 census was performed May 4, 1940, and shows Peggy as 8 months old, making her birth September, or October, 1939.
Sources
Brother Billy R.'s obit gives his sister, Peggy J age:0 on the 1940 census as being Peggy Devore of Bentonville Find A Grave: Memorial #47590446
"United States Census, 1940," database with images, FamilySearch (https://familysearch.org/ark:/61903/3:1:3QS7-89MB-BWKF?cc=2000219&wc=QZXT-RXV%3A790106001%2C790103502%2C795987701%2C795987702 : accessed 16 November 2021), Ohio > Adams > Sprigg Township > 1-17 Sprigg Township E of State Highway 41, Bentonville (part) > image 20 of 22; citing 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.
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