Spoooooky

This story isn't actually mine, but some co-workers and I were discussing the whole ghost thing a few days ago and his story came out. Basically, there is a little girl who keeps showing up in his apartment. He admits that he has seen her generally when he's tired and about ready to go to bed, but he's still awake. There was also one instance in the middle of the day when he caught her out of the corner of his eye. He usually sees her out of the corner of his eye, but he says she is definitely there. She looks to be about 10 years old, and he says he feels like she watches him until he notices her and then she disappears.