Some characters should be infertile

[Kljunas]

There should be but game engine works differently as someone pointed out in CK 2 less kids are born but less die in infancy. So infertile characters should either very rare or people should make more babies ( which is not gonna happen because that would explode courts with additional courtiers and make save files too big).

I know birthrates are low to compensate for the low child mortality, and that's fine, but I still feel it's extremely rare for rulers to die childless, unless they are very young.