Skeleton turns invisible after player death

I was shot by a Skeleton next to my bed. When I respawned the Skeleton was still there but had turned invisible. So I was unable to fight it or at least to avoid its arrows. I walked away from my bed and it followed me. But when I respawned after dying again, it was next to my bed again. This turned my savegame unplayable. I had a backup so it's no problem. But that shouldn't happen in the final release.