http://www.writerscafe.org/writers/Phil%20Kuhlman/
It's the story called "Friend". It's only a couple of paragraphs, so it's a nice fun creepy read.
And I know how you feel about creepy kids giggling in the middle of the night. I deal with sleep paralysis a lot since my surgery/cancer stuff, and one of the things I hear nearly each time I have an "episode" is kids crying or giggling. If I didn't know what it was I'd be even more creeped out than I already get by it.
