The wrong daughter

"Do you have a sister, Ms. Fairview?" The little girl's question, in all its buttery innocence, slices through me, and the answer catches in my throat. It isn't as simple as yes or no. It hasn't been, in nearly sixteen years. The evening Caitlin and Olivia's parents leave them to go to a dinner party, both girls are bubbling with excitement. At ages 10 and 13, they are at last old enough to stay home alone. After all, in their idyllic town no one...