CP doesn't really worsen
It's just they way your body is. My sister was born with it. She had seizures when she was a couple days old, had to have speech therapy and corrective casts on her legs and lazy eye correction and other stuff as a little kid. And all of it worked great and nobody thinks she has any disabilities at all anymore unless she tells you.
She also has a thing where if she's not looking at an object in her hand she can't describe it's shape. It's weird.