Besides that, i also think it is a different thing: You do have to eat, we are eating meet for 10000 years and we need it much more than watching a circus show. Also killing an animal quick and fast is also a different thing than dominating an animal for a show.
"A healthy vegan diet can meet all your nutrient needs at any stage of life including when you are pregnant, breastfeeding or for older adults." -- http://www.dietitians.ca/Your-Health/Nutrition-A-Z/Vegetaria...
No, you don't need meat; You want it.
A vegan diet for children is borderline child abuse in my opinion.
To your point though, difficult in what respect? I've been doing this since I was 9 and haven't had any issues. The most common concerns I hear are nutritional (protein, iron, calcium, B12) and convenience (restaurants, grocery stores, birthday cakes, etc). But I'm curious as to what your specific concerns are.