is there something about the irish, that we know this (first cousin, second cousins and removed ..)?

I really do think so. In the case of my family, I know many of my quite distant relatives (third cousins, 2C2R, 2C1R) which would be unusual in the US. In the US people are more mobile, often moving far from their parents' home on reaching adulthood, and losing contact with all but their immediate family. Here, at a family celebration or a funeral, if the "focus" of the event is an elderly person, and 1st cousins are represented in that generation, the younger generation can be up to third (or greater) cousins.