The Mary on Main Street? Their son Edward J C Bullock lists his occupation as "genealogist" in the 1930 Warren city directory. I wonder what became of him?
That Mary died in 1932. See this:
"Rhode Island, Deaths and Burials, 1802-1950," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:F8H7-YNW : accessed 13 July 2015), Mary Wild Bullock, 18 Apr 1932; citing Warren, Rhode Island, reference 26; FHL microfilm 1,941,476.
The 1925 Rhode Island census lists her as widowed with three children(the 1900 census lists her husband as George - the address is the same as listed above):
George S Bulloch50Edward J Bulloch45Elizabeth S Bulloch44