It sounds like you’re describing someone who was widely considered exceptionally beautiful at a young age and are now curious about how they look at 20.
However, you haven’t provided a specific person’s name or any additional information. If you have a particular person in mind, please provide their name, and I can try to give you more information about them at the age of 20, based on the information available up to my last knowledge update in September 2021.
The little kid has fully matured. Recently, she and her boyfriend were spotted in the south of France. They are obviously really in love, as seen by the trip photos.