flu, if you have the resources to create a trust fund for your kid(s), then I would suggest staggering payments if it will include lump-sum payments. Perhaps some at age 21, some at 25 and some at 30, etc.
The vast majority of “kids” at ALL these ages are too immature to handle large sums of money to make it last and could easily end up broke and even addicted to drugs. And if their sights are set on big ticket items (house/condo, vehicle) they will still need a lot of “direction” so as not to get ripped off (make good decisions). “Socioeconomic level” has nothing to do with this. If anything, the kids who grew up at a higher socioeconomic level will more likely fall prey to societal ills, mooching partners and even swindlers, simply due to having more money at their disposal.
It’s one thing to talk to a 16-year old about how much things cost and quite another for an 18 or 21 year-old to have a $275,000 check in their hand, made out to them :=0