To whom does custody of the child belong: to her mother who remarried, or to her grandmother, or to the paternal uncle and aunt of her deceased father?

The custody of the daughter belongs to her mother, as long as the mother does not marry or have an impediment that prevents her from having custody. The one most entitled to custody after the mother is the mother of the mother (the maternal grandmother). The paternal aunts have no right to custody as long as the maternal grandmother is present, unless the latter has an impediment.