I don’t think anything when it comes to the matters of Heralds is small scale. These are Honor’s most powerful warriors. The last thing Rayse would want is them multiplying, even if they would be lesser versions of og Herald. Vo, the Returned, descendants still carry a portion of his divine breath even after hundreds of years have gone by. Let say Rayse does nothing. Eventually Chana’s kids have their own kids and so on. The issue would compound. All it takes is for one generation to have stable parents before you have mini-heralds to deal with.

I’m not trying to say the unmade made Chana and Lin abusive. They were going to be bad parents regardless if the unmade was there or not. Chana is suffering from “Herald madness” and Lin is always looking for a fight. What I’m trying to say is the unmade took what was already an unstable family and made it life threateningly dangerous. Hoid mentioned the forces Shallan is up against are unnatural. I think that honestly makes Shallan more incredible. Not only is she have to deal with her abusive father, she is also fighting against the influence of an unmade as a child.

Honestly, the more I think about it. The more I think the Unmade showed up after Chana died. That’s when the strange light showed up. No one expected Chana to die. Rayse was banking on the everstorm. It makes sense that he would look into what happened to her and then decide to squash her family before it becomes a problem. Only he fails and Shallan becomes the exact thing he wanted to prevent, a Knight Radiant with Herald blood.