Do the children of the deceased mother inherit her share of her deceased son's inheritance if the mother died after her son and his heirs?

The inheritance is divided as follows: The mother receives one-sixth due to the presence of lineal descendants and multiple siblings. The wife receives one-eighth. The two sons divide the remainder equally. Thus, the estate is divided into 48 shares: 8 for the mother, 6 for the wife, and 34 for the sons (17 for each). The brothers and sisters inherit nothing because they are excluded by the sons. However, they will inherit their mother's estate, which includes her share of her son's inheritance. It is advisable to refer inheritance matters to Sharia (definition) courts or to consult with scholars knowledgeable in these matters.