Спільний звук

A boy was home alone one night. Around 2:13 AM, he heard his mom call from downstairs: “Hey… come here for a second.” He got up, half-asleep, and started walking toward the stairs. But as he passed the bathroom, the door suddenly creaked open… and his mom grabbed his arm from inside. She looked terrified. “Don’t go down there,” she whispered. “I heard it too.” They both froze. Then, from downstairs… the voice came again: “Why aren’t you coming?”