Why Is The Power Of My Daughter's Eye Increasing?

Hi!! My daughter is 6+ years old. She had -5 in one eye and -3 in another since 2 years, now it had increased to -7 and -4. She is constantly using her glasses. I am concerned about her future days. Would the power come to normal? Or would it increase more? What to do in this case? How to take proper care of her eyes. Please advice.