Something I don't know about after all these years...

[Tobus]

If, as you say, there is a strong oral tradition in your family that points to a specific clan-- I'd follow that tradition.

That's what we've always done, and I'm comfortable with it. But it always stays at the back of my mind that it could be the other clan we originally came from. Or heck, the name is also associated with County Antrim, in northern Ireland! With no way to find out for sure, the only thing we can do is go with oral tradition.