Thank you for your query.
As your child is growing the power may increase but that will mainly the spherical. You need to give a good healthy, nutritious diet for a healthy vision. The diet should contain adequate amounts of things like carrot which are a good source of vitamin A
Ensure that your child wears her glasses regularly and does eye exercises to strengthen the muscles.
I hope I have answered your query to your satisfaction.
Wishing your daughter all the best.