I was wondering how it can be lawful, since presumably, it is technically assault. I know that assault can be legal, if it's consented to, and is therapeutic, as in surgery, or for cosmetic purposes, e.g., tattooing.
But these involve either adults giving consent, or children having consent given by parents, as in the case of surgery.
But clearly you can't consent to an assault such as tattooing, in a child. How does it become legal for MGM? Custom and practice, I guess.