Do the deceased son's daughters fall under the mandatory bequest (al-wasiyya al-wajiba) in which the grandfather established his grandson in place of his father, and does the grandson for whom the mandatory bequest is made fall within the one-third bequeathed to the sons' male children only, given that the deceased son's share does not exceed one-fourth?

A grandfather's bequest to one of his grandchildren, specifying a share equivalent to that of their father, is valid. According to the majority of scholars, the grandchild is treated as one of the sons in their share, whereas according to the Maliki school, they receive their father's share without being included in the overall distribution. If this share exceeds one-third, its execution is contingent upon the heirs' approval. The allocation of males in the bequest does not include females. If a testator makes multiple bequests whose total exceeds one-third, they are not enforceable unless the heirs approve them. If the heirs do not approve, the excess beyond one-third becomes void, and the beneficiaries of the bequests will share proportionally within the limits of the one-third. As for the grandson to whom a share equivalent to his father's is bequeathed, the default is that this falls within the one-third designated for the male sons of the sons, unless the testator's intention clearly indicates otherwise.