Is handing over a sum of money entrusted as an amanah (trust) to the disabled son's maternal aunt, along with the father's will to deliver it to the son upon marriage or for a beneficial matter, considered fulfilling the trust or a dereliction in preserving it?

If a father grants something to his young son, and the father takes possession of it on his behalf, the gift is valid and enforceable even if the father dies before the son takes possession of it upon reaching maturity. The heirs have no right to claim it. However, if the son was an adult and had not taken possession of the gift before the father died, the gift is null and void and reverts to the inheritance.

Therefore, the trustee of the gift must hand over the amount to the son if he is mature, or keep it for him until he reaches maturity. The trustee is not permitted to hand over the amount to anyone other than the legal guardian, nor is he permitted to invest the entrusted money without the permission of the guardian or legal agent.