Lizzie is one of 3 person on earth with a rare syndrome- she can't gain weight! She's 25 and weighs 40 pounds but hasn't let this stop her from waging a campaign against online bullying. Check out her TED talk: http://www.youtube.com/watch?v=c62Aqdlzvqk
She's the best. I feel really lucky to have gotten to spend some time with her.