Please see your Pediatrician
Your Pediatrician will look into her calcium, vitamin D status. If vitamin D levels are low (inadequate exposure to sunlight, vegetarian by diet) then she might need supplementation in correct dosage.
Even if everything is normal or its just a growing pain, you should give her daily calcium supplements
with vit D in recommended levels.
I suggest you see your doctor and get his advice. Till then you may try Ibuprofen
syrup in a dose of 7.5 mg/kg/ dose when pain is severe.
Hope my answer helps you.
Wish your daughter good health.