<p>My oldest D (17) and I are vegan while my D (14) is a vegetarian. There is a whole world of possibilities for food and protien that doesn’t involve animals at all. For example, this morning we had a tofu scramble with peppers, onions and veggie sausage wrapped in a tortilla - delicious and easy to make (saute the onions/veggies and then move to the edges of the pan, add a touch more oil and saute the crumbled tofu with seasoning to taste). Tonight I’m making a veggie pot pie that is amazing (younger D requested it as she’s coming home from a ski-trip tonight). I make fettucini alfredo with a sauce made of tofu, a little white wine, garlic, onion, some vegan butter and blend it, it is incredibly creamy and my son - the carnivore, prefers it to the real thing. My girls live on Boca chick’n patties that can be pan fried on microwaved - very tasty! Also, ground veggie crumbles can be blended into marinara sauce for spaghetti or mixed with sloppy joe sauce for sloppy joes. I have a ton of options so please feel free to PM me for any info. Also, as to vitamins, they come from plants - cows get their calcium from greens too 
I have great cookbooks I can recommend too. I’d let him follow his own path and discover new things along the way.</p>