All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
If your mother is poor, then your brothers, who are well-off, are obligated to spend on her, each according to his ability. As regards spending on their needy brother or any other relative, then there is a difference of opinion among the scholars about this matter, but the most preponderant opinion is that it is an obligation to spend on him if he is poor and if he is entitled to inherit from them in case of death, meaning that there is no one to prevent him from the inheritance. Therefore, your well-off brothers are obligated to spend on you and to carry this obligation until you will no longer be in need of their provision, either by earning your own living or having enough money, and it is your right to ask them to fulfill their obligation toward you.
However, we advise you to be patient as patience is a door to every good; for more benefit on the excellence of patience, please refer to Fataawa 85445 and 83577. Indeed, the provision is in the Hands of Allaah and whoever knows that his provision is in the Hands of Allaah, he should not be sad. Allaah Says (what means): {And there is no creature on earth but that upon Allaah is its provision, and He knows its place of dwelling and place of storage. All is in a clear register.}[Quran 11:6]
However, even though the provision is something that is decreed by Allaah, Allaah has ordered us to endeavor to achieve it and take the permissible means to obtain it. So, Islam urged us to endeavor to earn our living, and dispraised being lazy and slothful and begging people. Allaah Says (what means): {And when the prayer has been concluded, disperse within the land and seek from the bounty of Allaah, and remember Allaah often that you may succeed.}[Quran 62:10]
Moreover, Abu Hurayrah narrated that the Prophet said: “By Him in Whose Hand my life is, it is better for one of you to take a rope and collect firewood and carry it on his back (as a means of earning his living) than to ask someone for something and that person may give him or not.” [Al-Bukhari and Muslim]
Besides, Ibn ‘Umar narrated that the Prophet said: “The upper hand is better than the lower hand." (i.e. he who gives in charity is better than him who takes it).” [Al-Bukhari and Muslim]
Furthermore, ‘Umar said when ordering people to seek provision and urging them to work: “The sky does not rain gold or silver.”
Allaah Knows best.