Is the father obligated to compel his children to pay rent for the apartments they occupy in his building to achieve justice and clear his conscience, even though he does not need this rent and does not wish to burden his children with it?

A father must be just among his children when giving gifts, because the Prophet, peace and blessings be upon him, said: "Be mindful of Allah and be just among your children," and "Be equitable among your children in giving." This is unless there is a legitimate reason for favoritism, such as illness, a large family, or seeking knowledge.

If there is no legitimate reason, then equality between males and females in gift-giving is mandatory. If he has already transferred ownership of the apartments to the males, then he must either reclaim them from them, or divide them between them and the females, or give the females their value. If he only gifted their usufruct (right to use), then he must either gift the females something similar or its value, or reclaim the gift from the males, even if by imposing rent on them.