He died and left behind a wife and nephews and nieces
Question

                A man died and left behind a wife, but he did not have any children. He has brothers and one sister, who are all deceased, and they had children, males and females. How should the estate be divided?.
Praise be to Allah.If a man 
    dies and leaves behind a wife and nephews and nieces, and there are no other 
    heirs apart from these, then the wife gets one-quarter because there are no 
    children. The sons of his brothers get the rest by virtue of being male 
    relatives on the father’s side, and it should be divided equally among them. 
    The sons of his sister and the daughters of his brothers do not get 
    anything, because they are not among the male relatives on the father’s 
    side.  
Allaah says 
    concerning the inheritance of wives (interpretation of the meaning): 
“In 
    that which you leave, their (your wives) share is a fourth if you leave no 
    child”
[al-Nisa’ 
    4:12]
And the 
    Prophet  (peace and blessings of Allaah be upon him) said:  “Give the 
    shares of inheritance to those who are entitled to them, and whatever is 
    left goes to the closest male relative.” Narrated by al-Bukhaari (6732) and 
    Muslim (1615). This indicates that male relatives on the father’s side may 
    be entitled to inheritance, and that the closer relatives take precedence 
    over those who are more distantly related, and they inherit after the shares 
    of inheritance have been allocated, if anything is left for them. 
What is 
    meant by shares of inheritance is those that are stipulated such as one half 
    or one quarter or one eighth. 
And Allaah knows 
    best.