"United States Census, 1940," database with images, FamilySearch (https://www.familysearch.org/ark:/61903/1:1:K4N9-69L : 10 January 2021), Leo O'Halloran in household of Leo O'Halloran, Watertown, Middlesex, Massachusetts, United States; citing enumeration district (ED) 9-598, sheet 3B, line 51, family 52, 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 1620.
"United States, GenealogyBank Obituaries, 1980-2014," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:QKR5-D57K : accessed 20 March 2021), Col Leo D O'Halloran Jr, Massachusetts, United States, 16 Sep 2005; from "Recent Newspaper Obituaries (1977 - Today)," database, GenealogyBank.com (http://www.genealogybank.com : 2014); citing Watertown TAB & Press, born-digital text.
Daughter: "Texas Birth Index, 1903-1997," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:VDS2-JDB : 5 December 2014), Leo Daniel Ohalloran in entry for Elizabeth Erin Ohalloran, 07 Nov 1969; from "Texas Birth Index, 1903-1997," database and images, Ancestry (http://www.ancestry.com : 2005); citing Texas Department of State Health Services.
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