Interesting quirk in LoR

[FietsPomp]

When the oldest son is not the heir (which happens often because of the pink ribbon trait)
And when the younger son who is the heir has a claim, you can invite him to your court.

Ofcource i married him to my daughter matrilinially who is an Aztec Nestorian (im doing a weird game)

 

[Hastyr]

you can make your eldest son heir by giving him a special honorary title

 

[FietsPomp]

you can make your eldest son heir by giving him a special honorary title

Im not the ERE. This bug allows you to invite the ERE's heir and matrilinially marry him to anyone, effectively killing the ERE dynasty.