I was surprised to find wildly differing birthdates for Irish immigrant ancestors, but Radford and Betit's excellent Genealogist's Guide to Discovering Your Irish Ancestors said they often didn't know the year they were born. It just wasn't important in rural Ireland. Radford and Betit said Irish immigrants sometimes were 5, 10, or 15 years off their actual birth year, although the day and date were often more accurate. From censuses, tombstones, local histories, etc. I found birth years for an my Irish ancestors would range from 9 to 17 years, like 1813 to 1830. When one applied for a Civil War pension, the pension examiner said he "could not tell his age. We should judge him 52." Combine that with the fact that they kept using the same first names over and over (there were five Michael McMahons in a New Hampshire town of 1700 people), and it's no wonder we have such a hard time finding them. Robin in Maryland