Yeah. If that's it, now is the time to get on top of it, before it gets really bad.
The worst for us were the last few weeks of soccer season -- she wasn't getting enough rest. The good part about it is that permanent damage is not done by playing with the injury -- if you can stand the pain, exercise is actually better than no exercise. But the pain got really, really bad.
Then she had about 6 weeks of rest between soccer and basketball, and has been fine since.
If it's Osgood-Schlatter, that's not always the result, though. I posted about it on Facebook and a lot of people had stories about having to give up sports because of the pain.
PT helped, but I think it might have been linked to a specific growth spurt too -- it might kick in again if she's in an intense sport and has a growth spurt at the same time. We'll see.