Not only that but the calves would require a large percentage of that milk, and so a byproduct of dairy farms is often veal, at least for the male calves.

It's obvious but blew my mind when I was told that

Then after only 4-5 years of this they are slaughtered because the milk production begins to diminish.

They do tell it in school. What is meat. Vegan vegetarian.... Ethical working with animals ... 11-12 year old classes btw.