Wills and Testaments
Malik :: Book 37 : Hadith 37.10.9
Malik related to me from Ibn Shihab from Said ibn al-Musayyab that Uthman ibn Affan said, "If someone gives something to his small child who is not old enough to look after it himself, and in order that his gift might be permitted he makes the gift public and has it witnessed, the gift is permitted, even if the father keeps charge of it."
Malik said, "What is done in our community is that if a man gives his small child some gold or silver and then dies and he has it in his own keeping, the child has none of it unless the father set it aside in coin or placed it with a man to keep for the son. If he does that, it is permitted for the son."