Betrothal, but no Marriage.

[Servancour]

To me, the screenshots seems to be referring to different characters. The first screenshot seems to be of your daughter being married to the caliphs son. The second seems to be of another character in the court of a count.

Are the images related to the same marriage? Or different examples? Do you get the notification when both parties are of age (saying that the betrothed can marry)? If you go to your child's character interface, is the betrothal still in place? If so, are you able to go to the betrothed's interface and break the betrothal?

Would it be possible for you to upload your save game? It would make it easier for me to see what the problem is.

 

[Servancour]

The issue here is the OP has turned off the betrothed can marry alert.

Yes, this is indeed what I suspect is the case. Using the Outliner to the right should solve it. The game may not be very clear that you have to use this notification in order to marriage a betrothed couple. Might be something worth of looking into.