The kid, the video, the silencer do his parents know?

I stumbled across a video on YouTube of some kid maybe 11 to 13 (he was smart to never show his face) showing people how to make a silencer for his pellet rifle. I wonder do you know his parents are aware of that? And where did you think he learned it from? And do you figure because he took great care to not to show his face that maybe he should not be doing that? Lastly do you find that rather chilling what kids can find on the Internet? What else are they learning, pipe bomb 101?