How is the estate of the father and paternal aunt to be divided, and is zakat obligatory on the inheritance before or after its distribution, given that there are 8 sons, 15 grandsons, 3 daughters, 24 granddaughters, and a maternal sister of the deceased?

The children of the mother's brother do not inherit, nor does the mother's brother inherit when a daughter is present. As for any new inheritance for the deceased father, if it was his share from an old estate, it is divided among his heirs, including the son who died after him. The share of this son is then divided among his heirs. The father's estate is divided among his eight sons and three daughters by way of ta'sib (residuary heirship), with the male receiving the equivalent of the share of two females. There is nothing for the son's children (both male and female), nor for his sister from the mother's side.