Is it permissible for a grandmother to bequeath one-third of her estate to her needy grandchild, thereby reducing the inheritance of her heirs?

A grandmother's bequest of one-third of her wealth to her daughter's son is permissible and commendable, because he is a relative who is not an heir. Allah Almighty has commanded bequests to close relatives, stating: "Prescribed for you when death approaches any of you if he leaves behind wealth is a bequest to parents and near relatives according to what is honorable." However, the heir was excluded from this command by the Hadith (definition): "There is no bequest for an heir." The preponderant opinion is that a bequest to non-inheriting relatives is commendable, and this is the view of the majority of scholars.