On the first page (of 9) of death results for Dublin North I counted 24 deaths of children with the surname Taaffe.. most aged less than one. I was thinking that if the numbers were less that it would be possible to order a few likely certs. But with that number that's not an option.
Another idea might be to look for first names that appear in the family - i.e Rosanna, her husbands name (John?), other names that appear in later generations.. also Rosanna and her husband's father's names if you know them from their marriage cert.
Shane