Her body, her choice.
His body, his choice.
All there is to that, imo.
On the note of it healing, the holes don't always close up. They also don't always stay even as a girl grows. To some, that's not a big deal, but to others, it is.
For her sake, I hope she likes them.
Personally, I would wait for a child to ask before even thinking of piercings.