Is it permissible to reclaim the inheritance by force from the paternal uncle, after the grandfather’s injustice towards the father by depriving him of the inheritance, and the failure of all attempts at an amicable solution?

A father's division of his wealth among his children during his lifetime is considered a gift, not an inheritance. The preponderant opinion is that it is not permissible to prefer some children over others in giving, due to the Prophet's (peace be upon him) saying: "Fear Allah and be just among your children," and his saying: "Be equitable among your children in giving." Some scholars have used this as evidence for the obligation of equitable distribution and the invalidity of a gift if it is not so, while the majority of scholars hold that equitable distribution is recommended. Upon the death of the giver, scholars differ as to whether the gift remains valid or if it must be returned and divided equitably. It is advisable to refer these matters to the religious authorities to resolve disputes. The brothers are advised to fear Allah, reconcile among themselves, remember the transient nature of this world, and beware of animosity and discord.