She huffs. ‘But what about my hair?’

The strands on her scalp are damp with sweat. Honesty. I try to channel Gemma. ‘It’s a bit flat where it was squashed by the wig, but with a blow-dry, it’d be fab again.’

‘You’re wrong! It used to be blonde and soft, like Mum’s. Now it’s coarse and uneven and bleurgh.’

Casey turns away and I can see the back of her head. The regrowth is patchy in a few places, but most of the ageing rockers I’ve met would be over the moon if their hair transplants were half as lush.

‘It’ll be great. Hair is easy to fix.’

‘A hairdresser would laugh at me!’

‘No one would laugh, Casey. There are thousands of hairdressers in Bristol. We can find one who will transform your look.’

She gives me a sideways glance as I catch her up.

‘Mum says we can’t afford it.’

‘I’ll pay.’

‘Good hairdressers are expensive.’

‘It can’t be that bad.’

‘Like, a hundred quid or something.’ The way she looks at me now is different: like she’s testing me.

Another hundred quid is nothing on my over-extended credit card. What matters most is that she trusts me enough to believe I could help.

‘A total bargain, if it makes you happy.’

‘Plus colour on top. It costs less if it’s not all over. My friend had a blue streak put in and it is so cool.’

I’m being played. But, weirdly, I don’t care. ‘Hmm. What would your mum say?’

Casey sighs. ‘She’s so weird right now, she’d probably think shampoo would kill me. Or a hairdryer.’

‘Weird how?’

She shakes her head. ‘Nothing like as weird as you.’

‘Fair comment.’

But as we walk, I wonder what she meant. Angelica does seem stressed, and when she’s in a bad place, who cares for Casey? The hospital’s close, so if I don’t try again to get at the truth now, I might not get another chance. ‘Is your mum finding it hard, being here?’

Casey stares at the pavement as we walk. ‘A bit.’

‘How?’

There’s a long pause. ‘Like, yesterday . . . there was a dog in the hospital school.’

‘A guide dog?’

‘No, a therapy dog, we’re meant to stroke them or whatever, to chill out. But Mum saw the dog and she totally freaked out. And . . .’ She shakes her head.

‘You can tell me.’

‘No. She’s doing her best.’ Casey’s voice shuts me down.

But when we get to the hospital, she asks me if I’ll wait until her treatment is over. ‘After I’m finished, would you have time to take me to the classroom and say hi to my teacher?’

‘No sweat,’ I say, though the buzzing in my ears starts the second we arrive in the hospital lobby.

‘You could wait out in the garden while they zap me; it’s less medical out there, remember?’

Her automatic kindness makes my heart break a bit. ‘Brilliant idea.’

She nods, then looks down: she’s still carrying her wig. I wait for her to put it back on, but she takes out a cotton bag and rolls the wig up, before stowing it away.