Lily looked at the vent on her wall — a small iron grate near the floor. She nodded."Has it—" Nora stopped. Tried again. "Have you heard your name?"Lily was quiet for a moment. "It said something like my name," she said finally. "Once. But I think it was practicing. Like it was trying to get it right and wasn't sure yet."The way she said it — calm, observational — made Nora's skin contract."What did you do?""I put my pillow over the vent." Lily said this with the pragmatic efficiency of someone who had encountered a problem and addressed it. "It helped. You can't hear it as well."Nora crossed the room and looked at the vent. It was on the baseboard, iron, maybe four inches by six inches. A pillow was propped against the wall beside the desk.She bent down and looked at the grate.Behind it, the duct was dark. She could see nothing. She could feel nothing — no air movement, no warmth or cold.But she had the acute and complete sensation of being looked at.She straightened up. "You're going to switch rooms with Owen," she said. "Tonight. His room is at the front of the house."Lily did not protest, which told Nora something."Mom." Lily said it when Nora was at the door. "It's trying to understand us. That's what it feels like. Like it's learning."Nora turned around.Lily had turned back to her homework."Don't go upstairs alone," Nora said. "Either of you. Owen either. Okay?""Okay," said Lily.She said it with a matter-of-factness that was either very reassuring or very frightening, and Nora spent the rest of the evening unable to determine which.