Looking for any Mullen or Campbell left in Crossmolina after 1849/1850

Robert Mullen emigrated to US in 1849, born 1825. Arrived in NY.  Married Elizabeth Campell ( born 1825 in Mullenmore Ireland) there in 1851. (? if she is from Mullenmore parents William and Frances nee McMain Campbell) Roberts parents are James and Margaret.  Have been unable to find any siblings  or what happened to his parents. I have been assuming that they died during famine. Robert fought in the American Civil War and was wounded at Gettysburg. They had settled in Roxbury Massachusetts. He listed Crossmolina as where he lived on his enlistment papers for the US Army. Any info would help. Plus if any Mullen/Campbells left in Crossmolina they should know Elizabeth and Robert 's story. Believe her parents could have died in Kilmoremoy/Ballina. 

Would appreciate any help.