Your use of "vegetarian" and "animal protein" are unconventional. "Vegetarian" generally refers to someone that does not eat meat but does eat eggs and dairy, so when you said "vegetarian kids need animal protein", it implies they need meat. But meat is not essential for development; B12 is, and can be got from milk or eggs.
It's true anyone raising their child vegan ought to be aware of B12 deficiency. Time was when B12 could be got from dirt on vegetables pulled from the ground, but nowadays we're pretty finicky about cleanliness.
> The point is that study after study shows that with just a tiny portion of animal protein, they end up a whole lot smarter.
You're confusing two separate issues. The key factor is that treating malnourishment of impoverished and starving African children is beneficial. This has nothing to do with whether they are fed concentrated protein from animals or plants.
I'm not trying to suggest you aren't yourself a smart person, just that simply because you can't see the ill effects your actions cause doesn't mean they don't exist.