This may have been posted about before so I apologize if it's old news.
A little trick I discovered. When looking for a birth on the Irish Genealogy site you can use the father's surname and the mother's maiden name to bring up matches.
So here I am looking for Brophy births with mother Dalton. I put Brophy... then a space and.... Dalton. No date.
See my attached pic.
I do my query and it will bring up all possible matches. Of course this only works for those records where the maiden name has been included in the record on IR.
I hope this makes sense and is helpful

Mary Ann