Better be careful with this. I betrothed a family member (male) to the heiress of England (she only had sisters). It was not matrilineal. I was distracted when the marriage button came up and it was a matrilineal marriage. How annoying. It's because AI used to never change the betrothal to marriage. Now it can be very tricky. Ugh. That could've been my dynasty on the throne of England.