Got a seed where Deirdre got the same blood as well. Can't remember if you have logic that is supposed to prevent Sigurd and Deirdre from having the same major blood or not.

I can't be sure that not randomizing lords was the cause of the issue, but it seems like a good starting place to investigate.

(I'm dumb and forgot that major bloods are no longer blacklisted in 0.8.1. Or was that for future versions? I forget already.)