I got my parents to agree by giving them the facts about what really happens to our food, and what’s really in it. I did lots of research and I manage on my iPod how much iron and protein I need and if I am getting the amount I need. It was hard to convince them at first but they eventually gave in. Good luck
Being Vegan is sometimes very expensive I’ve been a vegetarian for 6 years and after a while you and your family and even your friends will learn to respect your decision.. especially if you educate yourself on the topic first.