I've been told, although I can't verify it, that all the Cairo's from Calabria were related. I know that this is only circumstancial evidence, but when my grandfather emigrated from Italy in 1888, he did leave a large family behind. I remember back in the 1950's that my Uncle Mike was in contact with our (great-)Uncle Mike. I'm not sure if he was still living in calabria or not. Thus I would not be surprised if we didn't turn out to be distantly related.