When I was a child I lived in a rented two-floor house. Both my parents worked so I was often alone when I came home from school.
One early evening when I came home the house was still dark.
I called out, "Mum?" and heard a voice say "Yeeeeees?" from upstairs.
I called my mum again, and again got the same "Yeeeeees?" reply.
I felt she was calling back at me and climbed up the stairs.
When I reached the first floor I called her once more and the voice "Yeeeeees?" came from the furthest room.
I felt both uneasy, but a strong urge to see my mother, and started to walk towards the room.
But just that moment I heard the front door downstairs open and my mother come in, carrying a lot of shopping bags.
"Sweetie, are you home?" my mother called in a cheery voice.
Hearing her voice made me feel instantly better and I turned back to go downstairs at once...but not before I had a quick glance towards the room.
While I watched from the top of the stairs, the door to the room slowly opened a crack.
For a brief moment, I saw something strange in there.
A pale face, staring at me.