With so many states involved it does make the situation a bit more complicated. What is not complicated is the need for a court order resting custody for the children in their best interest. I would think a custody petition should be filed as soon as possible so as not to upset the kids anymore thatn they have been upset and a lawyer should be hired to manage the minefield of different state issues.
You will need to speak with an experienced family law attorney to navigate the jurisdiction issue and to file the appropriate Petition to have an order issued. It sounds like the grandparents are also involved, so this will further complicate your case because there are standing issues as well. You will have a very difficult time without an attorney.
My response is based solely on the limited information contained in the question. It is not meant to substitute your attorney's advice.
I agree with my colleagues - you need to sit down with an experienced family law attorney as soon as possible. Although your order is in PA, it may not be an appropriate venue since neither you, the child or the father live here. It's unclear which grandparents had an objection to your moving her to GA or what state the grandparents live in. I think you should start with a GA lawyer for guidance, even though the case doesn't appear to be in GA's jurisdiction.
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