Must zakat be paid on money kept in trust for a minor until he reaches the legal age of maturity?

All praise is due to Allah, and may peace and blessing be upon the Messenger of Allah and his family. To proceed:

Zakat is obligatory on the property of orphans according to the most correct opinion of the scholars. Those tending to their affairs are the ones who would be responsible for paying the zakat from the property itself. The conservator should also use this money in business or trade for the orphans so that it is not all used up in paying zakat. If there are laws standing between the conservator and the money, and the situation is such that he is not able to do anything with the money, he cannot invest it and the conservator has no right to do anything with it himself, then my opinion would be that zakat is not obligatory in this case because one of the conditions for paying zakat is full ownership (tamam ul-mulk), which is achieved by having the money in one's possession and being able to dispose of it freely, which is lacking in this case.

And Allah Almighty is more Exalted and more Knowledgeable.