Just a little one. (Warning, may not actually be little)
As some of you may know, I have a rather distasteful younger brother. But, we have done some damage to each other (but mostly he to himself)

When he was a very little Maccybro (1 year old for Christs sake) and my mother was giving birth to my youngest sister (home birth) he managed to somehow crack his head open on the concrete steps in my garden. This now leaves my dad in a dilemma, he has to leave his partner giving birth to take 3 children, one of them screaming and bleeding from a head wound to the nearest hospital.

When we arrived (lucky for us there's a hospital just round the corner) there was a huge line, mostly old people who'd been suffering from heat or something (This is August) and this yet again presents my dad with a further problem, so using his awesome people skills he speaks up "Hello everyone, a lot of you probably won't appreciate this, but, my wife is giving birth right now, and my youngest son has done this, can I please cut in line?" and much kudos to the English people, he was allowed. Brother was seen, and sent to Ashford to get his head glued back together (The first of many times).

Fast forward a few years to the time I'm about 9, he's 6. I'd recently gotten into watching WWF (as young boys do) and neglected the warnings. Myself and brother made our own Wrestling Federation, which came to an end when I suplexed him into my bed and broke his nose.

He's also had a beer keg fall on his head and bled from his ears from another injury (Involving the previously mentioned concrete stairs and my youngest sister)

I also kicked my older-younger sister in the cunt because she pissed me off when I was 10 and she was 9, I thought it wouldn't hurt her as much.... boy was I wrong.

EDIT:
Maccybro has caused me much grievance as well, he pulled me out of bed while I was sleeping and sprained my arm, and recently threw his DS at my head hard enough for it to split in half, and fuck my ear quite well.
(Maccy Divided by 0 on, Sat 3 Jan 2009, 22:30, Reply)