If she dies and leaves behind a son and a daughter
Question

                A mother has two children. A male and a female. The father has passed away.He had nothing that we could inherit.How is the inheritance from our mother going to be splitted? Is it half for the daughter and half for the son? Or is it two thirds for the son and one third for the daughter?. As i said. we are one son and one daughter who inshallah is going to inherit from our beloved mother.
Praise be to Allah.
    If a man or a woman dies and leaves behind male and female 
    children, then the male gets the share of two females, because Allaah says 
    (interpretation of the meaning):

    “Allaah commands you as regards your children’s 
    (inheritance): to the male, a portion equal to that of two females”

    [al-Nisa’ 4:11]. 

    Based on that, if your mother dies and she has no heirs other 
    than you and your sister, i.e., she has no father or mother or grandfather, 
    then her estate is to be divided between you two, and you will have twice 
    what your sister has, so you will have two thirds and she will have one 
    third. If she has any other heir, he will take his share, then the rest is 
    to be divided between you and your sister as described above, i.e., you will 
    have twice what she has. 

    But we do not advise you to rush to ask about this now; 
    rather the estate should be looked at and divided according to the situation 
    at the time of death, as no one knows who will inherit from whom or what his 
    situation will be tomorrow except Allaah. 

    And Allaah knows best.