My older brother had a birth defect that left him missing half of one leg. They had him fitted with a prosthesis as soon as he was old enough to start walking. When he was about 7 or 8, he need surgery and was on crutches for a few weeks. The neighbor kid was a bully and kept trying to knock him off the crutches. After a few times of that, my brother took a crutch and cold conked the kid. Out cold. No more of that crap.
In later years, we would have neighborhood football games. My brother was on the small side so he didn't try to tackle anyone. He'd stick out that damned leg and trip you. It was like getting hit in the shins with a baseball bat. MAN that hurt.
