All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
Whoever dies and does not leave behind any heirs except his sister, then she inherits all his wealth; she inherits half of the inheritance [by virtue of the Islamic Law on inheritance] and the other half because there is no other heir. However, we advise you to take the case in details to the scholars in your country because it might be that there are other heirs whom you did not know.
Allaah knows best.