And if you save scum, RNG Jesus could bless you with a couple days waiting time if you lucky. Which also is a horrible way to play around it.
Unwise player save scum.
Wise player saves ***.
Joking aside i think the purpose of children as just successors to your playthrough is a bit boring. Having children as a noble should be a big deal, and you shouldn't just get unilateral control over them when you die. Having 10 kids should be perfectly possible but also a disaster as half your realm is divided up between jealous brother. You would be guaranteed a successor but also in a precarious and slightly weakened position.
I also think bandits and other players with no actual inheritance should want to have a lot of sons. Roleplaying as the 7 bandit brothers could be fun, if there was anything interesting about being a bandit that is.