I got a buddy that lost a leg due to cancer. He wears a prosthetic leg so you can't tell.
One night, he and another friend were out and got jumped by a bunch of dude's randomly. After getting punched, my other friend started yelling, "show him your leg, show him your leg!".
He showed his prosthetic leg and the dude's were shamed and then started trying to give them $50 as an apology.