Hello and thank you all for your replies,
Thanks shanew147, that's the family i'm trying to work on; the Francis (age 11) mentioned is my wife's grandfather. Turns out from talking to her elderly uncle last night that there was an older daughter who had married and moved out of before the Census, by the name of Margaret; married name was Kilfeather and moved to Sligo. Will have to start work on her soon.
Hello Smokestoomuch, thanks, yes, there are still relations in and around Finglas, but they are all quite elderly now and we are not in regular touch with their children (the perils of being on the other side of the world i suppose). It seems that many people remember Charlie Brennan and i think that he was a "local character". But, as you say, the problem is proving the link between the photo and the person. It seems to be accepted locally that the photo is Charlie; and i hear that there is a framed copy of the photo on the wall at Erins Isle labled as Charlie Brennan. So, its not news to the residents of Finglas that its Charlie.
I have also heard that it may take a year to get a response from pensions; lets hope we're lucky and its not that long.
I have been in touch with the Bureau of Military History, trying to get them interested and trying to see if they might take up the case to prove that this famous photo is actually a Finglas local boy. However, they have expressed no interest. My impression is that due to political and historical sensativities it is relatively recently that there has been an appreciation and reevaluation of the role of Irishmen in WW1. I was told by another source that the Bureau is basically only interested in the history of the Irish Army, post the foundation of the Republic only.
On another note, would someone be able to look up a grave in the old graveyard in Finglas? There is a Brennan family plot in the old graveyard in Finglas, the one with the ruined church. My father in law and his older brother told me that there is a plot where their father is buried, along with several other Brennan ancestors. There is a headstone with all the names of the half dozen or more Brennans interred there, with their father, Francis Brennan, being the last to be buried in that plot. They thought that the dates went back to the early 1800's or so. They saw it last about 2 years ago when they were both back in Finglas for their sister's funeral.
If anyone would have time to locate this grave and transcribe the names and dates it would be really much appreciated? It would help immensely with my research to have the names and dates of the earlier generations.
Christopher