Are grandchildren entitled to claim their mother's share of inheritance, which was divided during her father's lifetime, given that she passed away before him?

A person is permitted to divide their wealth during their lifetime, provided there is justice among the heirs and no one is harmed. This is considered a gift, not an inheritance. If a father allotted a share to your mother, it became her property and will transfer to her heirs after her death. Therefore, you have the right to claim it from your maternal uncle. However, if forty years have passed and there are indications that your mother or you yourselves relinquished this money, then you no longer have the right to claim it. In case of dispute, the Sharia court will rule on the matter.