I tried to tell them, but they said I was a nerd and a pain and sucking up to the teachers, so I shut up.

I leaned back on my chair like that. With the front legs off the ground and the back resting on the wall at home when I was watching TV. Dad went ballistic.

He told me about this kid he treats at the hospital. He had to operate on him and he won't walk again. He won't ever walk again. Dad says it happens often, but usually the kids just hurt their back when the chair slips out.

But sometimes it is worse. Like the ones who dive into shallow water. He operates on them and looks after them, too. He gets really upset about it sometimes - says how stupid it is. Says they always say they didn't realise that could happen. One minute being stupid and the rest of their lives ruined.

So he went ballistic when I did it at home. Asked me if I wanted to be one of his patients. I know how awful it is for them and their families.

I would never dive into shallow water, but I didn't realise that could happen to kids falling off chairs. But he says it is the sharp way the chair slides forward and the kid crashes back on the wall and floor, even crashing their heads against the wall and their necks can get snapped, or something like that.

So I tried to say something but they just laughed at me so I shut up. Now I feel really guilty. What if Ashley never walks again?

If I had kept saying that and told them about Dad's patient, might that have made them more careful.

I feel terrible.

I told them so.