The problem is that my son and heir fled to one of my vasals court and that vassal (the damned Duke of who Northumberland, God send him to hell) gave him the archibishpric of Durham? Now my son, who was the best ruler i was going to have so far (all stats at 20 or next to it) is not my heir any longer. Can i plot somethign so that he stops being the archbishop? If it was one of my direct vassals i couñd revoke his title, but he isnt. What can i do?