What is the ruling on the inheritance left by our father, knowing that he passed away before relinquishing his share of his mother's inheritance to his sisters, and did they take their full share or not?

The oppression of some heirs or the diminishing of their rights is an impermissible evil, and this is especially true concerning the vulnerable, such as orphans and women. The uncle who divided the inheritance and unjustly deprived his sisters must restore their full rights to them, or seek their forgiveness until they willingly agree to waive their rights, provided they are competent adults. Rights will be settled on the Day of Judgment. As for the questioner's inheritance from his father, it appears to be lawful as long as the division mentioned occurred with the mutual consent of the adult, competent individuals, because a division by mutual consent does not require strict equality, and differences in shares or the deprivation of some do not affect it as long as there is mutual consent. The father's intention to waive his share of his mother's inheritance in favor of his sisters does not entail any consequences for him or for the other heirs.