Is it permissible for a father to lend his money to his male children, excluding his female children, for profit over many years? And how is equality achieved if it is not permissible?

"Legally, a father must be just among his children in giving, and it is forbidden for him to favor or single out any of them without a valid reason. This includes lending; it is not permissible to single out one child with a loan without a valid reason, unless the others consent. Otherwise, he must lend the same amount to the rest of his children or reclaim the loan. Scholars differ on whether justice in gifting means equal distribution or giving the male twice the share of the female."