Help with inheritance

[Psychoclown34]

Been away from the game for a while, but still love it. I have a game going as Benevento. I've risen to the level of Kingdom and arranged a matrilineal marriage for my sister with a Byzantine duke. My sister currently has no title of her own, but I can easily arrange a duchy for her. But I want to be certain her titles will remain in my Kingdom and not go to the Byzantines. Preferably I'd like to see their duchy fall into my Kingdom. What's the best way to proceed?

I know their son will inherit both titles (should I give one to my sister), but I'm just not sure which liege will have his allegiance, me or the Byzantines?

 

[jonjowett]

Depending on which DLCs you have active, Byzantine duchies might be viceroyalties - meaning that they revert to the emperor on succession. (Eg: Is the duke styled as "minor viceroy"? If so, the duchy is a viceroyalty.) If they are viceroyalties, it'll be very very very hard to inherit them - but you will get a strong claim that you can press in war.

If you have Conclave active, there is a crown law that prevents duchies from being inherited by landed people outside your kingdom. (Not sure of the situation without Conclave - there amy or may not be something similar.) All you need to do to keep your sister's lands in your realm is to pass this law.

If you can't use the crown law option for whatever reason, you need to ensure that your sister dies before her husband. (Yes, I'm talking about murder. Try not to get caught.) Then, her firstborn child will inherit her duchy and become your vassal. When your brother-in-law dies, the same nephew might inherit his titles (depending on Byzantium's crown laws).