He is not a "foolish child", nor is he "a kid", he is a 27-year old adult.
You really think there should be a law (in which country?) that makes it illegal to be out of touch with family for a couple of weeks? Now that is what would be foolish.
Perhaps his sister, who started all this kerfuffle, is the one who should be charged with wasting "million of baht spent searching for this foolish child, along with countless hours of time and effort spent looking by various officials in various countries"!