The 1900 census says she has been married 41 years. It also says she came to the USA in 1856, so she and John may have married in the USA.
The 1915 & 1920 censuses enumerate Ann in the household where her son Walter J. is listed as the head of household.
"United States Census, 1900," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MSFZ-CXZ : accessed 9 July 2020), Walter Geoghegan in household of John Geoghegan, Borough of Brooklyn, Election District 6 New York City Ward 6, Kings, New York, United States; citing enumeration district (ED) 55, sheet 11A, family 199, NARA microfilm publication T623 (Washington, D.C.: National Archives and Records Administration, 1972.); FHL microfilm 1,241,044.
"New York State Census, 1915," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:K9RC-8XF : 8 November 2014), Walter J Geoghegan, New York, Kings, New York, United States; from "New York, State Census, 1915," database and images, Ancestry (http://www.ancestry.com : 2012); citing p. 28, line 43, state population census schedules, 1915, New York State Archives, Albany.
"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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