Pretty much says it all.  Created a custom Sov, played a previous game in which I married Nabaja.  (And why not... Assassin + Dominate not bad)  Now, starting a new game with the same Sov, on turn 1 go to the Dynasty screen, and he's still married to her, but she's dead.  I assume this means he can't remarry... so no offspring.

Save game: http://dl.dropbox.com/u/16152315/married_to_nabaja.EleSav

edit: p.s. this is the 2nd game with the same issue.  I noticed it in another game at around turn 20, & so started a brand new one.  Can post that other save (or even the save where Nabaja is still alive.)