Daniel (Donal) McCarthy (born about 1800) married Ellen Bohan (Bohane) on May 15, 1855 in Muintervara, County Cork

My mother Alice (McCarthy) Scheg went to Ireland to celebrate her 70th birthday.  I am planning on traveling to Ireland to celebrate my 70th in the summer of 2017 and want to focus on meeting any distant relatives or at least visiting the local areas of Ireland where my ancestors lived before they emigrated to the USA.  

When Daniel McCarthy and Ellen Bohan were married on May 15, 1855 in Muintervara, Cork, the witnesses were Eugene McCarthy and Richard Tobin.  I understand that the fathers normally witness the marriage. It is possible Eugene is Daniel's father but it also could be his brother.  A Eugene McCarthy was married to Johanna Murray on February 27, 1855, only a few months earlier, in the same parish.  The witnesses for Eugene and Johanna were Richard Tobin and Cornelius Murray.  Since Richard Tobin was a witness for both Daniel and Eugene, I am thinking that their father may have been deceased. Daniel was 55 years at the time of this marriage so his father would have been at least in his 70's.  

It is also possible Eugene as Daniel's father.  Daniel had three children Eugene born 1857, Daniel born 1858 and Mary born 1860.  I believe all were born in Auburn, Cayuga, New York. When Eugene, my great grandfather died on August 23, 1912 in Rochester, New York, there was a news article headlined "Well-known Auburn Businss ...."  

Since Daniel and Ellen were married on May 15, 1855 in Ireland and had their first child Eugene in 1857 in New York, USA, they must have emigrated sometime between 1855 and 1857.

Eugene c1857 married Mary Elizabeth Dunnigan (Donegan) on August 3, 1883.  They had Mary E. McCarthy, Agnes McCarthy and my grandfather Eugene Daniel McCarthy born June 10, 1889.  My brother is Daniel Eugene Scheg.

I am also wondering if Daniel c1800 might have been married previously. He is 55 years when he married Ellen and it is after the Great Famine.