I used that unified census finder to look for 407 West 47th, NY in 1930. There was no # 407 on West 47th, or else it wasn't enumerated. There were no Connollys on W 47th. Here is the link to ED 350, Manhattan, if you want to look:
https://www.familysearch.org/ark:/61903/3:1:33SQ-GRZB-N3S?i=3&wc=QZF4-MQJ%3A649437801%2C651606201%2C651702201%2C1589284557&cc=1810731Haven't looked for James Connollys in Manhattan yet.
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I also looked for 10 Adrian Ave, Bronx in 1930, but the stevemorse census finder didn't show a 10 Adrian Ave for 1930.
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When she provided the information for the trip in October 1928, Johanna Grant said her nearest relative in Ireland was her mother, Mrs Grant, in Knockanglass, Fethard, Co. Tipperary.
I don't know if you have this but, I think this is probably the family in 1911:
http://www.census.nationalarchives.ie/pages/1911/Tipperary/Cooleagh/Knockanglass/842561/house 8 in Knockanglass (Cooleagh, Tipperary)
Jane Grant, 50
Patrick 19
Hannie, 15
more details on the link.
and in 1901:
http://www.census.nationalarchives.ie/pages/1901/Tipperary/Cooleagh/Knockanglass/1704964/Richard Grant, 40
Jane 40
Thomas 18
Marget 16
Patrick 9
Johanna 5
if so, this is probably her birth, making her mother's maiden name Stephens
Superintendent Registrar's District: Cashel
Registrar's District: Killenaule
Union of Cashel, Co of Tipperary
Birth,
March 9, 1896, in Moyglass
Johanna [daughter of] Richard Grant, a tailor of Moyglass, and Jane Grant, formerly Stephens. informant: the father.
https://civilrecords.irishgenealogy.ie/churchrecords/details-civil/8e6c5b9778372?b=https%3A%2F%2Fcivilrecords.irishgenealogy.ie%2Fchurchrecords%2Fcivil-perform-search.jsp%3Fnamefm%3Dhanora%26namel%3Dgrant%26location%3DCashel%26yyfrom%3D1895%26yyto%3D1895%26type%3DB%26submit%3DSearchNow all you have to do is search a zillion Grant or Stephens marriages for one to a Rodgers and a Connolly.
Just on a hunch, I looked for Rodgers/Rogers births in Cashel RD for 1880 to 1896 and there were none. So probably no Rodgers families in that area. So that marriage, Grant-Rodgers or Stephens-Rodgers might be more likely in the US.
By the way, there are lots of Rodgers in Northern Ireland in general, in Kilkeel Parish and Registration District in particular.
There were 21 Connolly births in Cashel for that time period, so there were Connolly families in the area. But a cousin's maiden name wouldn't necessarily be Grant
or Stephens.