When my daughter began researching the Moughty family, we quickly confirmed what we expected...that it was an unusual surname. Of the five names in the Social Security Death Index, we knew three, one being my father-in-law, Bernard Moughty who died in 1980. The interesting thing we found, was that one of two unknown names was also a Bernard Moughty who died in 1960 in New York. It turned out that this Bernard had a son, Brian, which was also my husband's name. Coincidence? I still don't think so, although I still haven't proved the connection.
The first thing to understand about Irish naming patterns is that they are not set in stone. Some families used them, some didn't. If you see a pattern, it might suggest a connection. The naming pattern goes like this...
1st son - named after paternal grandfather
2nd son - named after maternal grandfather
3rd son - named after father
The first one is the one most usually seen and if you don't know the name of an individual's father, this could give you a hint.
I was researching a Dooley family for a client with the standard question...where in Ireland did the Dooley's come from? My client's ancestor was a Michael Dooley who lived in Ohio. His known sibling was a brother, Anthony, whose first child was born in New York. Michael's first son was named William, and when I researched Anthony, I discovered his first son was also named William. That provided a clue that both Michael and Anthony were sons of a William Dooley. From this hypothesis, I was able to develop a research plan. In this case it also helped that Anthony was a unusual given name when matched with Dooley (as opposed to Michael), reinforcing the importance of researching everyone in the family.
For my Moughty family, Bernard Moughty (my father-in-law) was the son of Patrick Moughty (the immigrant), who was the son of Bernard Moughty and Mary Lynn. Because the name was so unusual, I collected information on all of the Moughtys I found in records in Ireland. I had a large family of James and Maria Duggan whose first son was Patrick and second son was Bernard. I had some difficulty connecting this family until, on a visit to Westmeath, Jack Moughty (a still unconnected cousin) took us to the cemetery where my husband's great grandfather Bernard was buried. The large monument contained the names of the James and Maria family and Jack explained that James and Bernard were brothers. Their father, also Bernard was buried in the same grave.
One other interesting piece of information about the Bernard who married Mary Lynn (my husband's great grandfather). His death certificate stated that he was 94 when he died on 23 Jan 1954. However, I also had a baptismal certificate for Bernard Moughty, son of Bernard and Mary Glennon (same parents as James) which gave his baptismal date as 4 Dec 1854. That would have made him 99! When I went back to double check the baptismal information, I discovered a second Bernard Moughty with the same parents, baptized 25 Jun 1860. I never found a death record for the earlier Bernard (which would have pre-dated civil registration), but assume that he died. Always double check because it was not unusual to use the same name for a child born after the death of an earlier child.
I currently have eleven Bernard Moughty's in my database which I'm still trying to connect. If you see a naming pattern in your family evaluate it but remember, it's not proof, only a clue.