John is enumerate in the 1915 & 1920 censuses in the household headed by his brother Walter J. John's entry is immediately followed in each census by Helen & Charles, called "niece" and "nephew" (to Walter) and likely John's children.
"New York, New York City Births, 1846-1909," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:2WZY-44G : 11 February 2018), John Joseph Geoghegan in entry for Charles Francis Geoghegan, 15 Apr 1909; citing Manhattan, New York, New York, United States, reference cn 12197 New York Municipal Archives, New York; FHL microfilm 2,022,580.
"United States Census, 1910," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:M5MZ-V25 : accessed 9 July 2020), John Geoghegan, Brooklyn Ward 10, Kings, New York, United States; citing enumeration district (ED) ED 209, sheet 13B, family 383, NARA microfilm publication T624 (Washington D.C.: National Archives and Records Administration, 1982), roll 961; FHL microfilm 1,374,974.
"United States Census, 1920," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MJ5X-8VL : accessed 9 July 2020), Walter J Geoghegan, Brooklyn Assembly District 8, Kings, New York, United States; citing ED 452, sheet 7A, line 5, family 153, NARA microfilm publication T625 (Washington D.C.: National Archives and Records Administration, 1992), roll 1156; FHL microfilm 1,821,156.
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