Samantha’s eyes flicked to hers then—just for a heartbeat, just long enough to spark something that made Addison’s chest feel tight. Then Samantha laughed and threw a pillow at her. “Relax, Addie. You’re safe.”

Addison caught it, but her smile didn’t quite reach her eyes.

Later, after the noise of dinner and their parents faded into the house, they settled into their twin beds. Samantha was asleep quickly, her breaths even, her arm dangling off the side of the mattress.

But Addison lay awake, staring at the ceiling.

Her mind replayed the conversation, the way Samantha had joked so easily about something Addison had been carrying quietly for years. She...