When I was about twelve years old my family decided we were going to move to another town. My parents had bought some property out in the middle of nowhere and while we waited for them to complete the construction on our home, we moved into my grandparent's home.
My grandparents were only in state six months of the year and traveled back to the warm and sunny Arizona for the winter months. It was nearing Christmas time and in a two bedroom house we had my two biological sisters and my biological brother, crammed along with myself in one room. Since it was temporary, we made do with what we had.
One night I woke up to my sister getting out of bed. Whereas we only had two beds, I slept on the floor between her bed and my brother. I watched her get up and walk into the bathroom. I hadn't seen her come back, so when I saw a shadow stand at the foot of her bed, I figured it was her.
The odd thing about it was that she didn't just get back into bed like she would have any other time. I watched as she turned her back to the bed and just fell. I didn't hear a thud or anything so when I saw her hit the mattress, I became curious and reached over to touch her and make sure she was okay, only to discover there was no one there.