Who is The Child?

Who is the mystery child that appears out of nowhere in someone’s house, and what do they want?

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“The first thing that I noticed while I was alone in the house. I was an incredibly young latch key kid, was hearing my mom call my name out. This usually happened when I was in my room, and it would come from the kitchen on the other side of the apartment. Of course, after investigating and realizing that I was the only one home, I would always go back and hide in my room.”