‘I never see very much when I go to the clinic, Ash,’ he replied. ‘I go in and my doctor, Mr Sinclair, talks to me for a while in his office. Then the nurse – always the same nurse, chatty, friendly Sue who insists I call her Sue – she gives me an injection as I’m lying on a stretcher and then … well, I wake up in a private room. Mr Sinclair does some tests and then I come home. Bit boring, really. I’ve never even seen the operating theatre.’

‘That happens every time you go in to have your intestines … scrubbed, or whatever?’

‘Every time.’ Aiden kicked off from the side of the pool and floated on his back. ‘With the head injury I got at camp, it’s pretty much the same deal. Except this time, when I wake up Mr Sinclair gives me these … well, I suppose you’d call them intelligence tests. A whole bunch of strange questions. I suppose they’re checking to see if my brain’s still working as it should.’ He swept his arms out, tipped upright and trod water. ‘Everyone’s worried about my brain,’ he said. ‘You, Mum, Dad. I wish you wouldn’t. I reckon it’s working better than ever.’

Later, he knocked on my bedroom door.

‘Come and see this, Ash.’

I padded along behind him to his room. I was surprised by how he’d made it his own in such a short space of time. He had a projection of the solar system on his ceiling and this amazing miniature railway track. It was only a circle of a metre in diameter and just one train ran around it, but it was cute as anything. He’d been given it by Daniel at school, who’d had it as a kid, but said he didn’t want it anymore. I think I’m developing Mum and Dad’s passion for antiques, Aiden had told me.

But when I entered his room, it wasn’t any of that that took my breath away.

‘Oh, my God, Aiden,’ I said. ‘How did this happen?’

Almost every bit of material in his room – the bedclothes, a shirt that had been slung over a chair, a small rug next to his bed – had been ripped to pieces. It was a mess. And sitting in the centre of Aiden’s bed, surrounded by chaos, was Zorro, looking very pleased with himself. His tail wagged as he looked to Aiden for approval. I was able to work out the answer to my own question pretty quickly.

‘Mum is going to go mental,’ said Aiden.

Actually, Mum didn’t go mental. Not at first. She found it interesting and quizzed Aiden on the training techniques he’d employed. When he told her about the hand gestures he’d been using to give commands, she nodded.