Can you share their names and I will have a look as well. I can also look in the current telephone book for people with the same surnames still living in the same area's. It worked for me and I do know of others.
I do know if you have a decent year and parents names the General Registry Office in Dublin will do a bit of a search, I don't know what that costs. This is where you go for copies of birth certificates.www.groireland.ie
Have you looked at the 1911 Census?www.census.nationalarchives.ie