Ruling on wills which deprive some of one's children of their inheritance
Question

                i would like to know can a person cut out any of his childern from the inheritences. because their was some problems between him and his son-in-law. or use it as an excuse to cut his daughters out of the inheritences. can a person that has 10 childern .give one of them more then the other. while he is still alive put in his name a house and land and say it is not haram because it is his money and nobody has anything to do with it.
Praise be to Allah.This will is not permissible, because it goes 
          against the teachings of sharee’ah and is contrary to the justice and 
          fairness that Allaah has enjoined, especially among one's children. 
          Allaah says (interpretation of the meaning): 
“There 
          is a share for men and a share for women from what is left by parents 
          and those nearest related, whether, the property be small or large — 
          a legal share” 
[al-Nisaa’ 4:7]  
          
Then 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; if (there are) only daughters, 
          two or more, their share is two-thirds of the inheritance; if only one, 
          her share is a half. For parents, a sixth share of inheritance to each 
          if the deceased left children; if no children, and the parents are the 
          (only) heirs, the mother has a third; if the deceased left brothers 
          or (sisters), the mother has a sixth. (The distribution in all cases 
          is) after the payment of legacies he may have bequeathed or debts. You 
          know not which of them, whether your parents or your children, are nearest 
          to you in benefit; (these fixed shares) are ordained by Allaah. And 
          Allaah is Ever All‑Knower, All‑Wise” 
[al-Nisaa’ 4:11]  
          
Then Allaah warns those who go against this 
          division of legacies and play with it, by saying (interpretation of 
          the meaning); 
“And 
          whosoever disobeys Allaah and His Messenger (Muhammad), and transgresses 
          His limits, He will cast him into the Fire, to abide therein; and he 
          shall have a disgraceful torment”[al-Nisaa’ 
          4:14]  
Whoever deprives some of his children of their 
          inheritance, or gives some of them less than is their shar’i due, or 
          gives some more than is their shar’i due, or includes someone who is 
          not an heir among those who are given his legacy, is a sinner who is 
          guilty of committing a major sin. Also, it is not permissible to make 
          a will concerning one’s heir, because he has a share which is defined 
          by sharee’ah. Ahmad, Abu Dawood and al-Tirmidhi (may Allaah have mercy 
          on them) narrated from Abu Umaamah (may Allaah be pleased with him) 
          that the Messenger of Allaah  (peace 
          and blessings of Allaah be upon him) said: “Allaah has given everyone 
          who is entitled his rights, so there is no will concerning the heir.” 
          (Sunan al-Tirmidhi, 2046).  
          
If it is proven according to sharee’ah that 
          one of the children is a kaafir, e.g. by the fact that he does not pray, 
          at the time of the father’s death, then he is not an heir, even if instructions 
          to that effect are not mentioned in the will, because the Prophet  
          (peace and blessings of Allaah be upon him) said: “The Muslim does not 
          inherit from the kaafir and the kaafir does not inherit from the Muslim.” 
          (Saheeh – agreed upon).  
With regard to giving a gift to one of one's 
          children and not to the others for no shar’i reason, this is haraam 
          and is unfair, as it creates hatred in the children’s hearts towards 
          one another. The evidence (daleel) that it is forbidden is the hadeeth 
          narrated by al-Bukhaari and Muslim (may Allaah have mercy on them) from 
          al-Nu’maan ibn Basheer (may Allaah be pleased with him), that his father 
          came to the Prophet  (peace and 
          blessings of Allaah be upon him) and said: “I have given this son of 
          mine one of my slaves.” The Prophet  
          (peace and blessings of Allaah be upon him) said, “Have you given all 
          your children a similar gift?” He said, “No.” He said, “Then take it 
          back.” According to the version narrated by Muslim, he said: “Fear Allaah 
          and treat your children fairly.” So my father took back his gift.  
          
According to another version, he (may Allaah 
          be pleased with him) said: “My father took me to the Messenger of Allaah 
           (peace and blessings of Allaah 
          be upon him) and said, ‘O Messenger of Allaah, bear witness that I have 
          given al-Nu’maan such-and-such of my wealth.’ He said, ‘Have you given 
          all your children something similar to what you have given to al-Nu’maan?’ 
          He said, ‘No.’ He said, ‘Then let someone else bear witness.’ Then he 
          said, ‘Would you not like all your children to honour you equally?’ 
          He said, ‘Of course.’ He said, ‘Then you should not do that.’” (Muslim, 
          3059).  
But if the gift is being given to one of the children 
          for a shar’i reason, such as the child being poor, or in debt, or needing 
          medical treatment, then there is nothing wrong with that. And Allaah 
          knows best. May Allaah bless our Prophet Muhammad, and grant him peace.