Hi Suzanne,
My father is from Killasser, and had a sister with the exact same name as your great grandmother. I would be interested to hear if you have any information on any siblings of Mary, or of her parents.
The townland you refer to, Treanrevaghin, my father pronounced it as Treanrevagh, the same as what Cathy posted. If you got that townland from old documents, eg, the 1901 census, then it is possible that it was spelt differently on those documents, I know that is true for the townland name for my father's family on those census documents, the spelling varies a bit from what it was known in his time and in current days.
My father remembers an old man by the name of Michael Murphy from Treanrevagh. The age gap would fit with the Michael Murphy born in 1892, but obviously, there is no way for me to say for sure it was the same man, Murphy is quite a popular name here. Michael and his wife used to come to my father's house to visit on occassion. The story goes that Michael had two shotguns, his own and his brothers, and sold one to one of my uncles. Michael and his wife had no family of their own.
Michael had a sister, my father doesn't remember her first name, but remembers that she married the blacksmith by the name of Naughton, in the townland of Graffy. Naughton sold some of his blacksmith tools to my father's family, some of which are in use in my father's workshop to this day. My father remembers that Naughton and his wife (Michael Murphy's sister) had a daughter.
My father also remembers Murphys in the townland of Creggan, a Maggie Murphy and a "Beaut" Murphy. He had no idea what "Beaut's" real forename was. Maggie would have been about 25 years younger than the Maggie in your Grandparent's family. There may or may not be a link.
It may be a co-incidence, but with your Grandmother's maiden name being Cronnolly, there are Cronnolly's in Butte Montana with Irish heritage links in Mayo. Whether that is a link to the "beaut" Murphy or not, impossible to tell.
My father also remembers a family of Murphy's in the townland of Carrowbeg, doesn't know much about them, but thinks they were moved from Mayo up to Co. Meath by the government's Land Commission where they relocated farmers from poor farming areas to better land in the east of the country. I'd imagine there are public records on that which could be followed up on, which might give family member names etc.
There are not too many people alive from the era that would remember your Grandparent's family. My uncle might, and when I'm down with him next, I'll quiz him. If you have occassion to be in New Jersey, there is a Killasser native from that era living there, and I could give you his name, see what he remembers. One of our public representatives, Bernard Durkan,
http://www.finegael.ie/our-people/tds/bernard-durkan/
is from the Treanrevagh area. Might be worth popping him an email and see what he comes back with.
The event of "the gathering" which Cathy linked to would possibly be a great opportunity to find out more if you could get here for it, it is one of the few times that you might get people from far and wide coming together and you 'd never know what stories you'd hear.
Getting back to my Aunt's namesake, if you happen to have any more information on Mary Cronnolly's family I'd love to hear about it and see if there is a connection.
-Enda.