I searched the Irish Family History Foundation's database. It contains 12,000,000 surviving rcds for abt 65% of Irish counties. Rcds are increasingly sparse B4 1840, rare B4 1800. Unless the county is known, there is AT LEAST a 35% chance the ancestor's rcds aren't in the database.
For Bri(get) Mooney B 1914 in Kildare, I found 0 B rcds. There are NO B rcds for this name between 1894 and 1920. I find rcds in Cavan and Tyrone in 1912, but that's all.
B/M/D registration was civil after 1863 and comprehensive. The General Register Office keeps these rcds. Contact it at http://www.groireland.iehttp://www.groireland.ie.
Google the Foundation's name to lead you to this database. Register, opt to be notified as rcds are added and browse. Pls post your search results to my genforum msg.