In My Sister's Shadow

The twin sisters, Emma and Lila, had been joined at the hip since the moment they entered the world. They finished each other's sentences, wore matching socks well into adulthood, and could communicate entire conversations with a single glance. Their bond was as much a comfort to their small family as it was an oddity to everyone who observed them, and in their sleepy Northern California hometown of Westbridge, the sisters were as much a fixture as the redwood trees and the fog rolling in from the valley.
It started on a Thursday. Emma would always remember it as the worst Thursday of her life, though the sky that morning broke blue and clear, and the rhododendrons lining their street blushed with pink bouquets. Lila left early, as she always did, calling back to Emma in the kitchen as she cinched a scarf at the door. "Don't burn the toast, " she'd said, grinning, and Emma had laughed and promised as usual to remember.
But by midafternoon, Emma knew something had gone terribly wrong. Lila never missed her shifts at the Westbridge Library. Never. Not for illness-she'd once catalogued books with a 102-degree fever-or for the occasional family squabble or the lure of a sunny day. She was that reliable, that stubborn about keeping her word. When Emma called the library to check in, Mrs. Pennington, the head librarian, answered after a suspiciously long pause.
"I thought Lila was home sick, " she said, her voice heavy with something unspoken. "She didn't call in, but I figured maybe she got held up."