Technically, betrothal works in such a way that you can't marry a child, so I've changed the ages upon males and females reach adulthood to 14 and 12, respectively, as well. The only problem is that females will not have a guardian between the ages 12 and 16. I have increased the education focus speed to compensate for that, but if you've found a better alternative: Let me know!

People still get the "Coming of Age" event on their 16th birthday, when they get their education trait. I haven't found out how I can change that age. So, again, let me know, if you can help me out on that!

I have lower the adult age for males and females to 12 and in my one try it worked as it should.