Searching for my Irish roots

Hello everyone, I am looking for information on my Irish ancestors.  In all of my years searching my family tree I was told that 3 brothers came over from Ireland and 2 settled in Pennsylvania and the third went back and later came back and moved to Florida with his family. I have the Father listed as N. Andrew Wachob, no mother has ever been found. The three sons were John, James, and Joseph. I am told that they were from Donegal but I don't have any other information on that.  I would be greatful for any and all responses.