It's a great time to say more about children in the game. We finished all systems for genetics, attributes, and raising them(events about this are ready and works in the game), and we work on choices when they are adults.
At the start, we built in the game system of genetic characteristics. It means children inherit some of the attributes describing Player nad NPCs.
Each trait has an impact on gameplay - like "Ugly" makes fertility of character lower and "Attractive" in the opposite - make it higher.
So, when you choose a spouse for the king, or his sons and daughters, you should check which traits you will add to the bloodline because when you heir inherit the throne, you will face these attributes.
When your king has children, you are responsible for educating them. Your decisions in that kind of event will change non-genetic traits for them, also your relationship with children. Having a lot of children can make your kingdom more safely (more potential heirs and royal marriages to increase relations with other kings), but you spend more time taking care and defend them.
But why should you care about all of this? Because when the first king, Egbert, dies, you will play as his oldest son - with attributes that he earns in the raising process and as the genetics traits. The potential of your future ruler depends on your previous decisions.
After the king dies, the super-council Witan gathers up. Witan will decide whether your oldest son should be the new king. Witan is another significant system in the game, and for it, we will write separate note :)
When your king is alive, and his children grow up, you will take care of them too, but in the different events. If you have more sons, you must think about their negative emotions to the oldest brother (you can send them to the monastery, on wars, or something else). Your daughters will probably spouses to other kings, princes, or essential vassals. What can happen to them? You will make hard decisions between the happiness of your daughters and your power in alliances.
You also need to take special care of maintaining relationships with your bastards - they are not happy about being deprived of rights to the throne. If you do not treat your bastard well or his mother, he can back with the army of a foreign king and steal your throne.
And when your first son inherits the kingdom, he probably has brothers and sisters, and management of these relations will also be necessary - but it's another subject, and we will write more about it.
I hope you like it the way how we want to figure out maintaining this subject :) we will share more about mechanics under the Be the Ruler soon!