Well, what is cosmetic surgery anyway? Is fixing prominent ears in a little kid cosmetic surgery? I think it is and it isn't . It's totally cosmetic, but it's also important to fix so they don't get bullied in this dog-eat-dog world we seem to live in. SO, I would do an ear pinning (otoplasty) in a 6 or 7 year old kiddo. I would do a cleft lip repair in a 4 month old kiddo too. I would say that's more easily categorized as "reconstructive" but still. As far as doing breast implant surgery, that patient would need to be 18. For a breast reduction, though, i probably would do that as early as 15 or 16 with parental consent and support, of course. EACH CASE IS DIFFERENT. And that's the beauty of plastic & reconstructive surgery.
One of the surgeries that has grown immensely in popularity has been labiaplasty. This is one of those procedures that you would FOR SURE say: "Oh they have to be 21 for that!" But what about the young woman who is 15, has such enlarged labia that she can't wear a bathing suit or yoga pants, that she doesn't feel comfortable changing in the gym? Would she need psychological counseling for several years until she is 18 or 21, as opposed to a 1 hour surgical procedure done under IV sedation? A patient like that, with good parental support and education, I would feel perfectly comfortable performing a labiaplasty on at age 15. Case by case!