Why Is His Singing Putting /Him/ To Sleep?!

The longer he held her, the calmer she felt. She had never heard the song he sung to her, but it was soothing, and she soon felt herself able to breathe normally. She heard his humming slowly fade away and his hand in her hair slowed significantly, and she realized that he was falling back asleep. She felt awful that she had woken him up and she knew that he wouldn't feel rested if he slept in that sitting position for the rest of the night. She also knew that she probably wouldn't be able to go back to sleep, but that was no reason that he shouldn't get as much as possible. She tried to slowly detach herself from him, but as soon as she started to move, he jerked himself awake, instinctively pulling her closer. "Shhsshh. It's okay. You just need to lie down," Penny whispered, trying not to wake him up any more than necessary.