Legal Question in Family Law in Maryland

First, I would consult with your JAGC office to see if the military has an internal procedure for resolving this administratively, which would at least entitle you to resume your relationship with your daughter. If not, you need to file a court petition for custody, or if all you are seeking is visitation rights, for that. If your daughter was living in MD with you and the father's relocation from VA was within the past 6 months, you could still try to file the case in MD, which I assume would be preferable to chasing him to FL. Once the child has been there for 6 months MD may lose jurisdiction.