I fear that the problem with all this milk, nutrition, and other issues of children’s upbringing is that such adults are guided by the holy truth “the adult is better at knowing.” Compared to a child, you may be more experienced, but that doesn’t mean you can’t be wrong :) and with all these explanations you actually cover up your powerlessness. If you can't handle a child otherwise than violence - it's not the child's fault in this :) and children are not idiots and quite quickly understand all this. If, of course, you did not kill the self-esteem at all and did not develop the Stockholm syndrome, but this is a very serious case.