Ammar is standing near a crowded bridge in Mosul, shivering in the sunlight. He's a thin 16-year-old with haunted eyes. But he's not worried about himself. He says he has come to try to find help for his sister.
She's nine, and the ISIS attack that killed their parents as they tried to flee Mosul in June left her paralyzed.
"We were walking and they were firing from a building," Ammar says.
ISIS wanted to stop the civilians they used as human shields from leaving. There was a wall a few hundred yards away.