Zakah on rented properties

Q 4: My father (may Allah be merciful to him) left us two houses that are rented for a monthly sum of money. Is Zakah (obligatory charity) due on this sum that is given to the minors? I hope Your Eminence will clarify (Part No. 8; Page No. 179

A 4: If the rent of the two houses reaches a Nisab (the minimum amount on which Zakah is due) and a Hawl (one lunar year calculated from the time a property reaches the minimum amount upon which Zakah is due) has passed on it from the time of the lease contract, 2.5% of it should be given in Zakah by the minors' guardian. On the other hand, if the rent is spent for fulfilling the needs of the minors before a Hawl has passed on it, there is no Zakah due on it.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.