15-year-old Sara had considered suicide many times during her month-long ordeal. The old man she had been given to as a “gift” beat her frequently. He taunted her with videos of Islamic State militants beheading her neighbors. On two occasions she said he drew blood from her arm with a large syringe, making her feel weak and sickly. “They didn’t feed us much. I used to pass out a lot, but I would make trouble for him as much as possible and fight when I could,” Sara said, sitting under a tent in a makeshift camp for the displaced outside...