Somewhere, stowed in the far recesses of your mind, are all the memories of your youth. The first day you walked into school, your first birthday party, running around at recess and climbing the monkey bars, your first crush, memories of when you used to play out in the woods or in that abandoned building down the block... but deep down, in the furthest corners of your mind are other memories. Memories that aren't so happy. They're buried deep, but if you try really hard you may just glimpse them. Memories of other things. Things that used to keep you up all night with your blanket over your head. Things that used to scritch-scratch at your window and call you up from your bed. Things that used to make you cover your face with your pillow or yell for your mother or father to come rescue you.
Look hard, you'll find them.