Is the mother obligated to enable the heirs to receive the burial grant she received after the father's death, and is it permissible for her to refuse to do so while some of the heirs demand their share?

It is not permissible for an heir, even if she is the mother, to prevent the division of inheritance if one of the heirs requests it, and she must enable every heir to receive their right. If the mother insists on preventing it, we advise family mediation first. If she does not respond, there is no harm for the heirs to take the matter to the Sharia court, and this is not considered an act of disobedience, as the Sunnah indicates the permissibility of a son taking his father to court.