Williams Disease What Is The Disease Where You Grow Five Times Faster Than What You Should?

What is the disease where you grow five times faster than what you should? - williams disease

I only saw Benjemin button .. I know this is not the same, old and young are coming more and more .... but
It reminded me of the movie in which Robin Williams plays the aging baby too fast in 20 years or something like 80 and dies.
What is called the condition?