Ernestine
Novelette 10,175 words Recommended by 2 award/anthology sources
"Ernestine couldn’t understand why the only adult left who would help her was dead. There had been fewer of them around, strangers disappearing in the streets. Her neighbors, her mum. It wasn’t that they ran away, exactly. It’s just that they were no longer there. The last person she’d seen alive over the age of eighteen had been a cashier at the supermarket..."
Quasar links out; the story lives on Asimov's, where the author gets the click.