James Costello-Catherine Dempsey (Mariah's sister)

Interesting mix, 1900 census. Walcott Street, Brooklyn:

James, his wife Catherine, and her brother John Dempsey. Did James and Catherine have a son Bernard? If so, what happened to him?

Costellos, 1905 census, Bronx, NY. Bigger image to help figure out the street name.

David Costello is the child Nellie Grady brings to the US from Ireland when she emigrates.

Catherine dies Sept 1932. From Brooklyn Times Union:

another reference to brother Thomas ...