What are the mother’s right to son’s ashes?

My son signed over the POA to his girlfriend prior to his recent death. She did not let me speak to see my son while on his death bed. She only notified me after he passed. She has disappeared and neglected to arrange for cremation. His body has been at the morgue for a month now. I was notified yesterday that she surfaced and had him cremated. There are no assets or property to dispute. I want only the ashes of my son and she refuses. Does she have legal right to his remains?