Typically in Georgia any rights of the grandparents flow through the natural parent, and at the parent's discretion. However, it appears that you have significant ties to the child, and possibly that moving the child would not be in the child's best interests.
Depending on all the details, including the age of the child, the amount of contact the father has had over the last ten years, any support he has provided, and whether you were ever appointed legal guardian, there are a lot of options before you. I presume that the child is at least 11, and therefore the judge has to consider her point of view - if the child has reached 14, her opinion weighs far more heavily with the Court.
You could look to the juvenile court for guardianship - you could look to the Superior Court for full custody (if there is a prior court order) or you could even look to adopt. I almost always recommend that you take the girl to a family counselor - that will give you at a minimum an idea of what may be in her best interests, and from a third-party perspective.
I wish you all the best of luck.
If you have additional questions or concerns, please feel free to contact me directly firstname.lastname@example.org.
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