How is the inheritance divided among the heirs: (a son - a mother - a wife - 3 full brothers - 3 full sisters)?

If the deceased left behind only a mother, a wife, a son, and brothers and sisters, then the wife receives one-eighth due to the presence of a lineal descendant. The mother receives one-sixth due to the presence of a lineal descendant and a plurality of siblings. The remainder goes to the son by virtue of ta'sib (residuary heirship). The full brothers and sisters receive nothing, as they are excluded by the son.

Thus, the inheritance is divided into 24 shares: 4 shares for the mother, 3 shares for the wife, and 17 shares for the son.