This is a good question. It is very important to start prevention and treatment of Acne as soon as possible. Inflammatory red pimples may hurt people socially and leave life long scars which hard to treat. Young people like your daughter should start using and mild Acne acne cleanser twice a day. Depending on the type and severity of the Acne they usually need to start to use a low percentage Benzoyl peroxide gel in the evening. You can refer to the free download MDacne app for short video tutorials.