One thing that I've wondered about is when you speak to Moriarty and he finds out James is your dad, he talks about seeing you and James for the first time, and says "just your father, his brotherhood of steel friend, and you, the svckling babe..." I've still not got that far into the main questline, so don't know if this is revealed later, but is it ever mentioned who the BoS friend is?

Star Paladin Cross.

Great, thanks