In my family it's widely regarded as a fact - an obscure fact, but a fact nonetheless - that one of my mother's great-great grandfathers was also the great-great grandfather of my dad.
Civil marriage records do indeed reveal that both great-great grandfathers had the same name and were from the same parish -- though the townland is different.
However, using the "are my parents related" feature on gedcom, the results say that my parents are not related. I am baffled.
What say the genealogists here?