[Gus Berges]

My friend's concern is that if the child, a majority of age individual, but mentally immature, gets that kind of money, he would foolishly spend it on items that are of not much value and even potentially harmful (think sportbike, sportscar, lavish gifts, etc.), hence his concern about what would happen if his child were to have immediate access to such funds.

You two have confirmed my suspicion/original thought: legally it's the child's money and it's the father's fault that his child is this immature as he's the one who raised him. Gotta find an elegant way of letting my bud know that he did not get it "all right" with raising his child. Kid is a good kid (respectful, no drugs, no problems, etc.), but immature/very shielded from reality/somewhat spoiled.