Gemma smiles, but in a sad way. ‘Unfortunately, my husband died. Almost two years ago now.’

My scalp starts to tingle and I get that horrible sensation like my skull’s too small for my brain. ‘Did he have a brain tumour, like me?’

‘No. It was a blood cancer. And they tried everything. The medical teams here are amazing. I wouldn’t come back if I didn’t believe that.’

That’s the thing. The doctors can be amazing, but you can still die. A year ago, when the specialists found my tumour, they said mine was treatable. So I wasn’t that scared then. I even called it Bob, to make it less horrible. But since Bob started growing again, the consultants talk about reducing its effects: stopping cysts forming, battling the damage he can do to my eyesight, my hearing, my growth.

They never say the word death, but they don’t not say it, either.

‘Are you OK, Casey?’

‘I’m sorry about your husband.’

‘Thank you. What else do you want to know about Bear? Or you can ask me anything about the hospital. I’ll answer you as honestly as I can.’

I’m thinking about Ram, my friend from the hospital in Birmingham, who was funny and brave and much, much stronger than me, but died two days after Christmas. And I’m remembering the Aussie vlogger whose videos taught me how to tie the scarves. She survived till her sixteenth birthday but ‘lost her battle’ three days later.

‘Oh, another thing for your article, Casey,’ Gemma says. ‘Bear is a very good listener. And he never tells.’

‘Obviously. He’s a dog. He can’t speak.’

She smiles. ‘Good point. But, Casey, there are play therapists here if you feel sad. Or your mum could book to see a counsellor, if she’s worried about anything.’

I know all about the counsellors. But loads of people have talked to Mum about her worries and it’s only made them worse.

‘We should go back to the classroom now,’ I say.

‘You’re right. But . . . I’ll be here next week, if there’s anything you want to chat about. And I do mean anything.’

What happens when someone dies in front of you? If I die, who will make sure Mum is OK? Do you believe in ghosts, and do you think I could come back as one?

My scalp itches and I go to scratch through the horrible dead texture of my wig. I can’t take it off till I leave Bristol, but I could get my real hair done for when I go home. ‘Um, I do have a question. Not for the article, but . . . I love your hair – who is your hairdresser?’

‘Oh.’ She reaches up to touch the waves that sit on her shoulders. ‘His name’s Pepe and he works at a salon near where I live, close to the suspension bridge. He’s the best.’

‘My hair – not the wig, but my real hair – is finally growing longer and I’d quite like to get a haircut in a fancy salon while I’m here.’