Is it considered a sin or a shortcoming to hold a brother accountable or to demand the division of inheritance, knowing that this contradicts the deceased father's will for the younger brother to manage the agricultural land and take care of the family's affairs?

The inherited land belongs to all heirs, and each heir has the right to dispose of their rightful share. The father's will prohibiting the heirs from disposing of the land after his death is Islamically invalid. If the father bequeathed something from his wealth to his child, it is considered a bequest to an heir, which is impermissible unless the other heirs consent. If a dispute arises, the matter should be referred to the Sharia court.