MD has sole jurisdiction, assuming the mother lives there and has been there since the order. If that's the case, VA can't touch it until everyone moves away from MD or MD voluntarily gives up jurisdiction. I don't think there's much chance of MD giving up jurisdiction if the mother is there, since MD has at least as much connection with, and evidence about, the child as Virginia does. It's usually better to concentrate on the substance of a custody case rather than picking a long-shot fight over jurisdiction.
Jurisdiction over child custody and visitation issues lies with the court in the county and state where the child resides, not where the child goes to school or daycare. IF in fact the child "resides" exactly 50% of the time with each parent in a different state (i.e., spends an equal number of 24 hour periods in your physical care as in the mother's physical care) AND this was an INITIAL child custody petition (i.e., no court had previously exercised jurisdiction), then the initial case could be filed either in VA or MD. HOWEVER, where the MD court has already assumed jurisdiction of the matter and issued orders concerning custody and the child's residency has not changed to Virginia (at best, the child has a dual residency), then any modification proceeding should be filed in Maryland. If you gain primary physical custody of the child in that proceeding, then you could file a Petition for Registration of that foreign order with the VA courts.
I don't know whether there would be any advantage to trying to fight to have the case transferred to VA first because I am not licensed in MD and, therefore, not familiar with MD law concerning child custody modification. Similarly, an attorney who only practices in MD and, therefore, is unfamiliar with VA law on modification probably could not answer that portion of your question either. So, I would suggest that you find a family law attorney located either in VA, MD, or DC who is licensed in and practices in both jurisdictions (VA & MD) and schedule a consultation with them to discuss the merits of your actual custody case in detail and assist you in determining the best course for you.
This response does not create an attorney-client relationship and is intended for general information purposes only.
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