One time my wife started breathing and shaking violently in her sleep, to the point that it woke me up. I could tell she was having a bad dream so I shook her shoulder gently and started whispering for her to wake up. She finally did and I told her that everything would be okay and tried to calm her nerves.

She seemed to be calming down, but then suddenly breathed in very sharply and started staring wide eyed past me. I asked her what was wrong, and she gently whispered, “It’s right behind you...” I turned around and there was nothing there. Before I could turn back and tell her that, she let out the most bloodcurdling scream that I’ve ever heard. Her mom who was a few rooms over came in and turned on the lights and helped me convince her that nothing was there and that she was just dreaming. After a few minutes of consoling her she went straight back to sleep. I however stayed up for a few hours longer trying to erase that scream from my mind.