All mothers who have teenage daughters believe that those daughters are great beauties. As a result, teenage daughters don't put a lot of stock into what their mothers have to say. At different ages, teen girls have various issues with looks and body image. The reasons are many. On the other hand, some girls manage to be balanced and confident and concern themselves with being healthy and happy, rather than focusing on "beauty," which is temporary. Instead of harping on your daughter's great beauty, focus instead on her interests and talents. Those things are far more valuable and will go a long way to building her confidence.