Do the sons and daughters of brothers and sisters who died before the deceased inherit?

The children of a sister (both male and female) and the daughters of a brother are not heirs. However, the sons of a full brother are heirs as 'Asabah bi-al-Nafs (agnatic heirs). If a woman dies leaving two sons of a full brother as her only heirs, the inheritance is divided equally between them. Finally, this answer is not sufficient; the matter should be referred to the Sharia courts or discussed directly with a scholar knowledgeable in these matters.