Speaking as a person that has had theirs done three times for various reasons
, it would seem a belly piercing may be an alternative. But, 15 is, in my opinion, WAY too young for a tongue piercing. Personally as a punishment, I would make her take it out, let it close and not ruin your reunion entirely! And, if she is that set on having a tongue piercing, she can have it redone when she is 18+. GOOD LUCK!