Fire Emblem 4 - Editing mothers of child units with Nightmare?

[BumroyV2]

Firstly, I apologize if this is in the wrong place. I'm new to the forums, but I figured this would be a great place to ask this.

I'm curious as to whether or not you can use Nightmare 2 to change what mothers the child units have. Specifically, I'm wondering if Sety could be Adean's son and Lester become Furry's son. I know there are modules to change siblings, but I can't seem to find anything explicitly stating mothers being changed.

And yes, I know some people might consider this sacrilege and I fully expect any relevant events to be bugged out or even completely broken, but I'd like to see if it's possible.