I realized during my first file that the court wizard in solitude was always sleeping no matter what time of day it was. I always wondered why but didn't really bother to find out until I started my second file and did "The Wolf Queen Awakened" quest. After I told the Jarl's assistant that Potema was taken care of I noticed Sybille who was standing behind the Jarls assistant went straight to her room after the quest said complete. She went straight to sleep at 10:00 A.M. and i believed this is what triggered her coma like behavior. This seems odd seeing as she has nothing to do with this quest.
I am aware that this is not a major thing at all. You can still wake her up and talk to her as normal however she will continue to sleep regardless. I just noticed this as curious behavior that involved completing this specific quest and thought i'd make note of it.