A. He is probably right. Giving an infant Diet Coke is probably just as bad as giving them milk that is flavored with Nestle Quik. That doesn't make it okay. Instead, it is a good argument for why you shouldn't give either to a baby.
The only benefit of giving Nestle Nesquik is that it does have some added calcium and some other vitamins and minerals. On the other hand, it also has a lot of added sugar. And Nesquik products are not all caffeine free either.
So at this age, you are best off giving your baby either breast milk or an iron fortified infant formula, water, and up to 4-6 ounces of 100% fruit juice.
Another way to think about it is to consider if there are any good reasons to give an infant soda or flavored milk. If there aren't, besides the fact that she may like the way it tastes, then don't give it.
And don't believe the argument that 'just a little won't hurt.' It is hard enough to raise healthy eaters, and it really doesn't help to get them started early liking junk foods or foods with little nutritional value.