According to the description on YouTube, this kid “walked it off.” That means it is acceptable to laugh. You know, like the person who took this video laughed. And since it’s an 11-year old skiing, you have to assume the person taking the video was his father. Thus, his reaction – “Shit,” Followed by muffled laughter and quickly turning off the video – is even funnier. If something bad had happened to the child, the videographer would have immediately destroyed his phone so that no one would have known that his first reaction was not concern.
I imagine that is the tough part about being a dad. On the one hand, somebody just fell down hilariously. On the other hand, your wife is going to kill you. And on another hand, your kid might be hurt. At least you got it on video.