Is it impermissible (haram) or permissible (halal) to differentiate in treatment between children by lending one of them money for a business and enjoying the profits, without lending the others similarly? And does the one who is harmed have the right to borrow the same amount for the same duration?

We have previously explained the ruling on favoring children in giving gifts in Fatwa No. 76743. The preponderant view is that lending is permissible if there is a need, otherwise it is not permissible except with the consent of the others. If there is no need, and you do not consent to it, then they should either lend a similar amount to the others or retract it. The profits of the gifted one belong to him because they are a separate increase, and this is the opinion of the majority of jurists. Parents should be keen on establishing equality between their children in everything, including emotional matters, as this is more conducive to righteousness. Children must adhere to good manners with their parents and treat them kindly, even if they treat them poorly.