Do the grandchildren of a daughter who died before her mother inherit their mother's share of the inheritance?

If your grandmother passed away after your mother, her inheritance goes to the Ashab al-Furood (Quranic heirs) and the Asabat (agnatic heirs). The closest among the Asabat is the closest male relative. If she has no heirs other than you and your sister, then you both inherit from the Dhawu al-Arham (relatives by blood and marriage, or uterine heirs). The estate must be divided through the Sharia courts.