I was in 7th grade and lived in a detached garage converted into a small 1 bedroom house with my mom and little sister. It was butted up to an alleyway behind a larger house of an older man. My sister and I shared the bedroom and the room had mirrored doors on the closet that took up the entire wall. We had a bunk bed to take up less space and I had the top bunk. One night, I woke up because I thought I heard my sister fumbling around out of bed. I turned over and looked into the mirror where I could see the entire room lit by dim moonlight. I see her sitting on the floor criss cross applesauce facing the mirror. "Sami, get back in bed. Mom will be mad if she catches you out of bed." I go to roll back over to go back to sleep. Not even 3 seconds later, I hear my sister cough directly below me and she is definitely not awake and on the floor. I immediately roll back over and she is no longer sitting on the floor. No one is there. Who the heck did I see?!