Distributing One’s Wealth As One Wishes
1-1-2001 | IslamWeb
Question:
Are there any restrictions on a Muslim distributing his wealth as he pleases during his life? The money consists of our father's own earnings and the earnings of his sons who lived together with him. The father in his lifetime distributed his property unequally among two sons, saying that their earnings were not equal. Can one brother, in the father's life or after his death, demand that the property be distributed to bring his share to fifty percent.
Answer:
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad 
is His slave and Messenger.
If the father wants to gift his children something, he should give them equal gifts corresponding to their shares of the inheritance. The Prophet Muhammad said: “Fear Allah (O believers!) and be just in dealing with your children.” [Al-Bukhari and Muslim]
Allah has clearly defined each one's share of the inheritance. Justice among the children makes them all equally obedient. The Prophet Muhammad said to Basheer Ibn Nu’man, the father ofNu’man Ibn Basheer 
: “Will you not be pleased that all of them [your children] become equal as far as obeying you?” [Muslim]
This justice is in what belongs to him. As for what he takes from his children, if he appropriates it [if it becomes his possession], it becomes the same as what he has earned from his own work. So he should be just in giving it out to them. But if he takes this from his children as a consignment, or as an investment for them from which he spends on them, he should then give it back to them according to what each one of them has originally given him.
Anyway, your father might be right or wrong in distributing these belongings. So, if he had taken money from you as a loan or as a consignment and had spent on you from it and when redistributing it again among you, he had distributed what belonged to him justly among you and had given out to each one of you what belonged to him, so this is undoubtedly just. But if you gave your father your earnings to appropriate them and spend on you from them, then it was preferable for him to be just and equitable in distributing them amongst you. But you must keep good faith in your father's deeds. However, the gift he did became effective as long as your father did not take it back before his death. After your father's death, his son should not ask for any right from his brother for what his father had given him, because it became his own property.
We ask Allah to bless you and us with an excellence end to our lives.
Allah knows best.