John Galvin-----Allegany Co. NY

Looking for info on John Galvin,who was in his thirties and born in Ireland in the 1850 US Census.John had a family and was living in Belfast, Allegany Co. NY and was a farmer.Also in the famliy were:(1850 census,all Galvins);Bridgett 30, b. Ireland,James 13, b. Ireland,Mary 11, b. Ireland,Margarett 9, b. NY,John 8, b. NY,Bridgett 5, b. NY,and Catherine(Jane) 1, b. NY. Sometime in the 50s the family broke-up.John Jr., Margarett and Jane went to Sugarcreek, Venango Co. PA to live with other Galvins.(The James Galvin family.)I would like to know where John senior lived before he came to Belfast and who his parents were.Also where he was from in Ireland. Any help would be greatly appreciated.----------------Terry