i raised 5 girls...and am raising a granddaughter now. its best to offer advise and give solid informed reasons FOR that advise. pros and cons...and have her do the same......dont make it a screaming match......grab something to drink and sit at the table calmly and talk....i DO know the harder you bristle against it and condemn it...the more youll push her to DO it outta spite and even though its something she wants at the moment, doing it for the wrong reason, she will hate it. Kids will do wht they do........be understanding and patient.....she just might see your way is best in a couple years