Problem with succesion in baronies

[KIMON]

Good morning to everyone.

In my game as duke of byzantine empire i faced following problem:
Succesion law is agnatic primogeniture.I gave 2 baronies to my 2 brothers.One of them gave birth only to girls and therefore
he had no male succesor.Suddenly i saw that his heir was his brother and not me - the ruler.Every time i closed the game i
noticed that heir was changing...is this a bug?has anybody else noticed such a thing?

thanks in advance for your answers

best regards

 

[Cerogravian]

When you say "the heir was changing", do you mean it was jumping back and forth between his father (you) and his brother, or was it even less rational than that?
It would, as always, be grand if you have a save where we could reproduce this to see what's going on.