A father trading with some of his children

Q: I have seven sons and five daughters and I work in trade. My elder two sons have worked with me for ten years. After I spent money on them and paid their marriage expenses and they had children, they demanded a certain percentage of the next profit or to assign a fixed salary for them. They asked me to do so for I asked one of them who is a teacher and earns 7,000 Riyals per month to resign from his work so he could work with me in trade. I handed all my money over to them to dispose of as they want and did not prevent them from anything they wanted.However, I did not single them out for anything. It is worth mentioning that the youngest of my children is one year old. I have two wives and perhaps I will have other children. I fear that I might treat any of my children who work with me in business unjustly because they have children as I have. At the same time, I do not like to treat my young children unjustly if I give something to those who work with me. Could you kindly advise me in this regard.

A: There is no harm to fix monthly salaries for them in the future in return for the efforts they exert in business provided that it is equal to the amount given to their peers. (Part No. 16; Page No. 239) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.