She has been kidnapped.  The neighbor, a kindly older man with a talent for making indigestible, watery lemonade, invited her in for a glass.  He lives right next door.  She sees him everyday.  Being well brought up, she couldn’t refuse.  It’s after school but before her parents get home from work.  The sunlight is sticky through a gray ceiling of clouds.  Once she’s in the kitchen, the neighbor spikes her lemonade with Valium he’s saved after his wife’s funeral.  She gets drowsy, tries to flee, but can’t make it to the door.  Now she’s strapped to the neighbor’s bed.  He calls her by the dead’s name and feeds her the same watery lemonade the dead drank by the quart before she died.  He washes her body, thinks of how long this one will last, and is glad.

The same problem exists as in the murder hypothesis: why has there been no outcry?  Why is her picture not plastered throughout the school, the neighborhood, everyone questioned?

Unless her parents sanctioned the kidnapping.  They know the neighbor, his decline into dementia, and, due to some repressed desire, the desire not to be saddled with an uncommunicative teenager like they once were, they allowed this abduction to take place. 

But wouldn't somebody say something?