Lep,
Joihn Gallagher's parents were Martin and Mary Gallagher nee Donohoe/Donaghue.
Their children were ...
Patrick, b.Sligo c1838, married Lowell, Ma, USA 1873
Ellen, b.Sligo c1840, married Ontario, Canada 1862
John b Sligo c1842, married Blyth, Northumberland 1864
James bSligo c1846, married Sunderland, Co Durham 1870
Michael b.Ire. c1848,m. Bishop Auckland, Co Durham 1869
William b.Ireland c1850, m. Silksworth, Co Durham, 1876
Edward b. Newcastle, Northumberland 1852,m Silksworth 1876.
Jane b Newcastle 1857. died in infancy.
Mary b.c1820 Ire, died Ryhope, Co Durham 1874
Martin b.Ire, c1812, died Silksworth 1884.
Martin was married/alone on Blyth, Northumberland, 1851 Census.
Mary and family, without Martin are in Newcastle on C1861.
Patrick and his wife, Mary,(nee Moran) and Ellen and her husband, John McPaden, and the rest of them ( minus the deceased Mary and Jane) are all on English census 1881( All in County Durham, except John and his wife Mary O'Melia, who stayed in Northumberland)
So, in summary, I have all their "footprints" in USA, Canada and England, but not a sign of then in Ireland/Sligo. (in spite of many visits and efforts of Irish pofessionals.
Michael Dixon
Newcastle