I am in Peaceful and Survivor Modes.  My game has crashed a couple of times today.  In a well established village, all of my farmers and fishermen have despawned.  I also found out that some penned sheep have despawned.  One was a wild pink sheep that I had renamed (sad face).  I don't know if the sheep despawning happened today or earlier as they are behind some buildings.  Regarding the villagers, I had interacted with them earlier today and was in the process of changing the role of a librarian.  Since the despawning, the remaining villagers had started to breed and I have many babies running all over the place.  I have exited the game and completely relaunched multiple times.