Спільний звук

Then, not long before I got to Chiang Rai city, something made me shiver: a sound. Very faint, very clear, and completely separate from whatever was playing through my speakers. Heh. Heh heh heh. A child's laugh. Quiet, small, and close by — somewhere in the car, or just outside the window. It came twice, maybe three times. And whatever was playing on my phone at that moment, there was nothing in it that sounded anything like that. I didn't stop. I didn't say a word. I just kept driving.