What is the ruling on the inheritance of the estate of the deceased "S", given that his two sisters were not given their share of their father's inheritance?

The two brothers must return the money their two sisters are owed—if the sisters are alive—or to their heirs—if they are deceased. The sisters' right is not forfeited by the death of either brother or by the passage of time. Brother (S) must return what he owes his two sisters, and whatever exceeded his share in the estate of his first wife, before her estate is divided among her heirs.