Casey predicted this, so I go into the spiel we rehearsed during the walk back. ‘I talked to the hairdresser about it, and the colours are safe. He even did an allergy patch test to make sure it’d be safe.’

‘What?’

Casey lifts the lock of hair curled behind her ear to show where the stylist applied a dot of colour with a cotton bud. ‘I don’t think you can even see it any more.’

‘You let him poison her?’ Angelica spits out the words at me, and I flinch.

Casey looks stricken. ‘It’s not poison. And it’s not DL’s fault. I said I wanted the patch test. Even though I knew you’d spoil it!’

‘Casey, leave us alone, please.’

‘But Mum—’

‘No arguments. Go to your room. Now.’

Casey shakes her head, but does as she’s told.

When the door shuts behind her, I prepare to take the flak. ‘Angelica, I’m sorry if I did the wrong thing, but you weren’t there and Casey wanted—’

All the blood has left her face, so she’s ominously pale. ‘What gives you the right to let some stranger damage my daughter’s body?’

‘It was the tiniest bit of dye. It won’t have done her any harm.’

‘Really? Did you qualify in chemistry or medicine in the years when you were missing in action?’

‘Of course not. But those dyes are used on millions of people every day. You can even use them at home.’

‘You’re also allowed to smoke, Dan, even though it gives you lung cancer. You’re allowed to drink alcohol, which screws your liver; and to eat crappy burgers full of antibiotics and trans fats; and drive cars that chuck out pollution. Because governments don’t care about the little people, all that matters is big business and shareholders and—’

I raise my hands. ‘Hold on. We’re talking about a laid-back hairdresser at a vegan salon, not a plot by Big Pharma.’

She scoffs. ‘Don’t patronize me. You have no bloody idea what it’s been like fighting to get a diagnosis, fighting to get the right treatment. Do you know she’d had headaches for six months and had to collapse in class before anyone took her seriously?’

‘I didn’t know that, no.’

‘I failed her; she might have had treatment sooner if I’d pushed harder for a diagnosis. I can’t let that happen again.’

‘You didn’t fail her, you’re a brilliant mum—’

‘How would you know? You have no idea what being a parent involves. I don’t even understand why you’ve let us stay with you. Is it because Glastonbury isn’t running this year and you thought playing at being a daddy would pass the time?’

‘No. I’ve never claimed to be any good at families. But Casey asked for help.’

‘I should have stopped this. I knew you’d put her in danger.’

As Angelica rants and rages, it’s becoming clearer that her response is way out of proportion.

‘Have you talked to anyone about your worries?’

‘Oh piss off, Dan. Don’t make out this is my problem.’ She shakes her head and stomps into the kitchen area, grabbing a Bag for Life and starting to fill it with food from the fridge.