Alta, I think the disease you’re referring to is called Scheuermann’s disease. Scheuermann’s disease is a relatively common condition that is often diagnosed when x-rays are taken for other things. There is a big range of severity, but most cases have a good prognosis. What you about it depends on the severity of the curvature, but usually we advice children to reduce weight-bearing stress and to avoid strenuous activities. Good luck.
PS. If you a bit more info on it, mail me at netdoc@mweb.co.za and I’ll cut and paste you something.