My habitually boisterous half-sister is quieter than usual today, and instead of tearing around the place with Beavis yapping at her heels, I find her curled up on the sofa in the office, her nose in a book.

‘What are you reading?’ I ask, only to be struck dumb with surprise when she lifts it up to show me.

‘Evangeline And … The Time Machine,’ she reads, her words succinct but laborious. Then, when I simply gawp and say nothing, she adds, ‘Can you read it to me, please, Gee-nie?’

‘Oh, I’m not sure if I—’ I stop myself before the lie comes out. Of course I’m not too busy to read my new favourite person a story, even if it happens to be one starring a character based on me.

‘Budge up, then, Beavis,’ I say, and Tui chuckles affectionately as she lifts the little dog on to the floor. Then, almost as soon as I’ve sat down, she snuggles herself against me and pops a thumb into her mouth, the fingers of her other hand already searching for strands of my long hair to play with. It takes some effort, but I manage to push my voice far enough past the emotion that has gathered like a lump in my throat to begin the story. It is the first Evangeline And … book that David ever wrote, and it’s also my favourite.

‘Once upon a time, on a day soaked by rain, something very peculiar happened on a train.

A baby was born, right there on the floor, as if she’d appeared through a secret trapdoor.

Her hair was dark and her eyes were blue, but she wasn’t like me and she wasn’t like you.

This child was special, a wish come true, and boy did she have some things to do …’

‘Eyes like yours,’ Tui says, removing her thumb from her mouth as she gazes up at me. ‘Blue eyes.’

‘That’s right,’ I croak.

‘And like the sea,’ she adds, almost as an afterthought, but instead of replying, I continue to read.

‘With a whoosh from the engine and a squeal from the brakes, the great chugging train gave a groan and a shake.

Passengers hopped off and scurried away, everyone in a hurry, no time to delay.

The station fell quiet, and darkness arrived, when suddenly the silence was shattered by cries.

“What’s that?” cooed a pigeon, who had stopped to eat crumbs.

But nobody answered, no dads and no mums.’

Tui starts laughing again, hiccupping over her words as she points out, quite rightly, that pigeons cannot talk.

‘What do you think they would say if they could?’ I ask, and she screws up her eyes as she thinks it through.

‘Give me food?’ she suggests, and I have to laugh because she looks suddenly so serious.

‘Shall I read more?’

‘Uh-huh.’