I ask Elle what she’s been reading, and she asks me about gaming. I tell her that I just ranked up on Fairy Hunters, and she describes a series of books about an undercover alchemist. It’s set in a boarding school, like Harry Potter, and sounds really cool. We agree to have a three-day sleepover, where we binge on our favourite TV shows and films over half-term, and never change out of our pyjamas.

Later, when we stop for some food, Elle gets a message. ‘It’s your dad,’ she says, frowning, showing me her screen. ‘He wants you to look at your phone.’

That’s weird. Why would Dad message Elle? As soon as I see the stream of missed calls, voice messages and texts I know something’s wrong.

Dad: [Missed Call]

Dad: Saff, can you call me as soon as you get this?

Dad: [Missed Call]

Dad: [Missed Call]

Dad: Can you catch the next train home?

I know something big has happened, and I know when I find out that everything will be different.

I grab Elle’s hand and squeeze, like maybe it’ll stop time. She squeezes back. I wordlessly hand her my phone and wait for her to tell me what to do.

‘We’ll go now, OK?’ she says, before turning to the others to explain. ‘See you later, yeah?’

Abir and Izzy nod solemnly. I hear them whisper to Elle and ask her what’s going on, but I don’t hear her response. I don’t even say goodbye.

We leave in a rush, our food half eaten, and head to the Tube station.

I quickly text Dad before we go on the Underground. My hands are shaking.

‘Shall we ring your dad first?’ Elle asks.

I shake my head. I can’t here. Not now. I need everything to stop, just for a little while. Because the truth is, I don’t want to know what Dad has to say.

Saff: Getting on the Tube. I’ll ring you from the train. Be about 20 mins.

Elle holds my hand the whole way down, even as we go through the barriers.

Four stops to King’s Cross. Four stops for me to imagine the worst. Dad must be OK. I don’t have any grandparents, or aunts and uncles, apart from Mum’s sister . . . Is it Mum?

One. Mum cycles everywhere. Did she get hit by a car? Does she wear a helmet? I can’t remember.

Elle and I don’t speak. She just squeezes my arm every few moments. I don’t cry, but my heart is beating so fast I feel like I can’t breathe.

The Tube is too hot. I might pass out.

Two. Maybe she just tripped and broke a leg, and I’m overthinking it all? Dad’s just ringing to make sure I don’t go straight to her flat. Right?