I am a descendant of the McCallions from Culdaff. My great great grandfather John McCallion was born there in 1805. My great grandfather was his son Michael who spent most of his life in Scotland after marrying in Culdaff in 1866. As the names John, Michael and William have come down thru recent generations I suspect there were at least 2 brothers as there were a John and William McCallion recorded as having sons called John in 1867 and 1866 respectively.
In 1866 a Denis Mcallion and a William McCallion were recorded witnesses at my great grandfather's marriage in Culdaff. I suspect William might have been a brother and Denis a cousin, as he is recorded as being the son of Michael and having himself married in 1862.
There are also records of a Bernard, married 1864, a Patrick married 1863 and a James born 1832. I don't know whether these were siblings of Denis or of Michael, or offspring from another McCallion family.
if any of your local Culdaff knowledge can help me in my own search for earlier antecedents of Culdaff McCallion, I'd be glad to hear from you or any other browsers.