The heel-prick test, yes. They had taken a spot of blood from Mia’s heel when she was only a few days old, like they did with every newborn in the country. I had flinched when the thing like a staple gun had punctured her snow-white skin, so much worse than if it were piercing my own. A card was pressed to this tiny new wound and then lifted away to reveal a roundel of red. Now there were results. They hadn’t told me to expect results.

‘Yes, I’m here. Do you phone everyone with their results?’

‘Not unless there’s something, you know, definite to say. In Mia’s case they are inconclusive, which means we need to do more tests. Can you come to Atherton General tomorrow morning at eleven?’

‘The hospital?’

‘Yes, Atherton General, a bit past Clyde Hill … Fourth floor, paediatric outpatients’ reception. They’ll know to expect you.’

‘But what are the tests for?’ My stomach twisted and complained.

‘Her levels look a bit abnormal.’ There was a pause and paper shuffle. ‘For cystic fibrosis. I’m putting you on hold for a moment.’

The soft thump of blood drummed its quick new tune in my ears as I googled:

Cystic fibrosis – A genetic disease in which the lungs and digestive system become clogged with thick and sticky mucus …

Stomach pain …

Trouble breathing …

Must be managed with a time-consuming, daily regimen of medication and physiotherapy …

Over the years, the lungs become increasingly damaged and eventually stop working properly …

Debbie Carfax, twenty-three, was diagnosed with cystic fibrosis at the age of two and has been told she has less than …

Catching the common cold could kill this young man with cystic fibrosis as he waits for a life-saving lung transplant …

End-stage cystic fibrosis and how to manage the final days …

One in every 2,500 babies born in the UK has cystic fibrosis …

Average age of death …

Like drowning …

Just breathe.

A piece of hold music droned on, vanilla and classical, chosen to calm interminable situations.

I could feel the adrenalin rise inside me. Everything sharpening, narrowing, ready for flight as I stared at that single question.

Her levels looked abnormal.

I understood that there was a level to everything.

Under the right level, you drowned.

Above the right level, you overflowed.

Finally, a new crackle as the hold music was killed.

‘Yvonne says it’ll be something called a sweat test. You’ll need to bring lots of blankets for the baby to make her sweat. Do remember that. Blankets. And maybe some snacks and mags to pass the time?’ I had no time to reply before she said, ‘And make sure that your husband is with you. Have you got the address? Paediatric outpatients …’

‘Yes. Thank you.’

‘Best of luck.’ And with that, Kirsty was gone.

I hung up, the appointment details scribbled on the back of a tea-bag box with a free T-shirt promotion.