I have John Costello born 1827 in Ardtarmon, Maugherow, Sligo married to Margaret O'Boyle 11 Apr 1850 at Transfiguration RC Church, New York City. (((Margaret O'Boyle was the first O'Boyle to emigrate from Ireland in 1843. She paid the way for her parents and unwed siblings to follow her in 1848.)))
John and Margaret had the followng children: Patrick John Joseph Costello born 13 Mar 1851 Brigid Teresa Costello 15 Sep 1853, she died 1891 Matthew Costello 26 June 1860. He died 1923.
This family are not directly descended to me, but connected through my O'Boyle line.