William Fitzgerald and Ellen Burke

I am researching this couple from Ireland. I'm not sure where they came from.  I have found several William Fitzgeralds and Ellen Bourkes. I do know for sure that William and Ellen had  Catherine (Kitty)  about 1836 and a son John in 1838. I believe they were baptized in Murroe, Cashel & Emly. I cannot find a residence for them. The baptism handwriting matches a wedding of a William Fitzgerald and Ellen Bourke in 1836 for the same parish. The family followed somebody I believe to Canada between July 1838 and 1841. Their next child Patrick was born in Canada in 1841 in Hungerford. Other children were William, Michael, Johanna, Edward and Ellen. William and Ellen along with many of their children are buried a short distance from my home. 

Beside them in Hungerford in 1842 was a John Fitzgerald and his family. I believe that this John's father John was Possibly a Peter Robinson settler in 1825. So I believe there is a connection here. At the time that they lived in Hungerford in John's home there was an older Mical. 

I would like to know whom Williams parents were and his siblings. 

Any help or suggestions would be greatly appreciated.