HI Chris, I have found that birthdates can be problematic, especially when one is dealing with birthdates reported by someone else (as on a death certificate), or even self reported (as in birthdates given by a woman to the census taker -- because women did lie about their ages). I have a death certificate for my great, great grandfather that I know is the proper certificate, and yet, the birthdate/age given is off by about ten years. Since your grandfather was closer in time to Patrick and Hannah, and presumably might have heard stories or other information to support that photo, maybe you should at least start by exploring that lead? Can you check records in Knockbrack? Good luck! Hilary