Legality of helping a minor obtain a piercing needle?

So my sister has always wanted a piercing but my parents said no, so she couldn't get one because she is 14. She started dating my once friend, and he either bought or helped her buy a piercing needle online. It isn't on her credit card so I'm pretty sure he outright bought it. It was shipped to his address and he gave it to her sometime, probably at school because she was able to smuggle it home and pierce herself on the inside of the nose and wear the piercing around and show it to people at school. I'm wondering about the legality of all this. Thanks.