The next morning Edie is very quiet. She’s quiet while we pack – despite the sheer horror of trying to get all our stuff into two teeny-weeny little wheelie bags. And she’s quiet all the way to the airport, while we say goodbye to the amazing New York skyline. She’s quiet at the terminal, while I manage to sweet-talk the lady at the check-in desk to give at least one of us a window seat, and while I spend about an hour choosing between all the major fashion magazines in the world for the two that I can afford to take home.

She’s building up to something again. She’s biding her time and as soon as we’re safely at thirty thousand feet over the Atlantic and I have nowhere else to go, she’s going to let it all out, I just know it. However, after two hours, two Vogues (US and French) and an episode of The Simpsons, when she still hasn’t said anything, I can’t take the tension any longer.

‘Er, Edie, is there something you need to tell me?’

She turns her head from the window to look at me. She’s still got the clouds in her eyes. Slowly, she focuses on me.

‘No. I don’t think so,’ she says.

I may have been dreading it for hours, but now I just need to know what it is.

‘About Jenny . . . ?’

She sighs. ‘Oh. About Jenny.’

Here we go. I don’t actually adopt the brace position, like you do when you’re about to crash, but I’m tempted. Edie on the subject of endangered rhino, or African villages without water or whatever, is a frightening experience. Edie on the subject of her own friend, who’s chosen to sing a song instead of comfort her own mother – well, I have to admit, I duck slightly.

‘I’ve been thinking,’ she says slowly.

‘Yeeees?’

‘I think I was wrong.’

‘Sorry?’ I say, shocked. I’ve never heard her say this before. And I’ve known her since we started secondary school.

‘After I’d stormed out of the theatre I came back to get you, but you weren’t there,’ she goes on. ‘Someone said you’d gone to see Jenny. I bet you were giving her some encouragement. Being a friend for her. I’m sure it’s what she needed. I didn’t do that. I feel a bit ashamed of myself, really.’

‘You do?’

Edie nods and looks at me sadly.

‘I’m always so busy working out what people ought to do. But I can’t change them. They are who they are. I love Jenny. She’s doing what’s right for her. I should just let her do it. Don’t you think? Nonie?’

I realise I’m staring. Just staring and not talking. I mean, Edie can surprise me, sure, but this is unreal. This isn’t Edie at all.

‘I don’t get it,’ I sigh.

This makes Edie look even sadder. ‘Really? God, am I so judgmental that you can’t even imagine me wanting to stay friends with Jenny?’

Yes. She has hit it on the button. But of course I can’t say so.

‘Not at all!’ I say. ‘Of course not. You’re amazing.’

She smiles at me.

‘And you’re lying. To be kind. Just like you always do, Nonie. I don’t mean you always lie – although you do a lot, you know. I mean, you’re always kind. You put friendship first. I should copy you more.’

Hello? Genius-girl here, the one who’s on every team at school, in every band and orchestra (when she’s allowed), who has personally raised enough money to OPEN A SCHOOL in Africa, wants to be more like me? What’s going on here?

‘Don’t look so shocked,’ she says. ‘I mean it. And I mean it about Jenny. She was incredible, doing that song. Gloria would want her to do it. I mean, I couldn’t let my mother live alone like that, but I’m not Jenny. Maybe I should just help her.’

I’m about to express more shock and disbelief, but I realise that this would be rude. Instead, I take a deep breath.

‘Cool,’ I say. ‘Fantastic.’

‘Really?’

Edie’s doubtful pout suddenly turns into a nervous smile, and then a grin. She hugs me. A bit awkwardly, because we’re sitting in really narrow airline seats and she’s not the world’s best hugger anyway, but at least she’s trying and it’s great. Then I realise I haven’t got to listen to several hours of ranting about Jenny, and that’s great too.

Five minutes later, a stewardess comes along to ask what we want to eat. I turn to ask Edie, but she’s fast asleep. Her face looks more peaceful than I’ve seen it for months. And prettier too. I decide she needs sleep more than airline food and leave her to it.

Which leaves me with several unexpected hours of thinking time to myself. I’m not necessarily very good at thinking time. If I think too much at the moment – unless it’s about Liam – I tend to think about Crow getting this job without me, or Mum and Vicente and losing our home, and I can’t bear to do too much of that right now.

I try watching a romcom on the mini screen in front of me, but it doesn’t work. In the end, I find myself picturing Isabelle’s apartment. How gorgeous it was. How full of memories of Harry. And it gradually occurs to me. This thing that’s been bothering me for ages. The thing that’s not right between them. Somehow, after the whole Edie-not-blaming-Jenny revelation, I can see things in a completely different light.

It’s not exactly a thrilling discovery about my brother. In fact, it’s pretty tragic in its way. I find myself poring over it for hours, wondering what I should do and wishing I could just forget all about it. The trouble is, I love Harry, and I can’t.