Luckily, Isabelle is staying at a hotel in London for the fashion shows, and not in our house. That would make what I have to say too totally difficult. Luckily, too, Liam agrees that I’m probably doing the right thing, when I explain it all to him. After my welcome home kiss. And my I-missed-you kiss. And several other kisses he can think of.

I find an appropriate moment when Harry’s home, but the house is quiet. I fortify myself with a double cappuccino and a whole packet of M&Ms. Harry’s in his room, packing to go to Milan for some shows, but seems pleased to see me. I feel such a traitor for what I’m about to say.

‘Er, Harry,’ I start, ‘you know that apartment that you and Isabelle are going to get in New York?’

‘Uh huh?’ he says, jamming some socks into his suitcase.

‘Well, how exactly do you imagine it? Exactly?’

It’s not quite the speech I had in mind. Not totally as fluent and articulate.

‘Well,’ he says, still fiddling with socks, ‘big, you know. Full of Issy’s stuff, naturally. All those textiles she collects. Big enough for you . . .’

‘That’s not what I meant,’ I say quickly. ‘I mean, what about your stuff? . . . How do you picture it?’

He looks up now, annoyed. ‘It’s not down to me. Issy’s got great taste. What d’you mean, Nonie?’

His sharp look softens when he sees how uncomfortable I am. He can tell this isn’t easy for me. His brow furrows.

‘Really. What do you mean?’

‘Well,’ I say, ‘I saw Isabelle in New York, of course, and I know if I’d asked her the same thing, she could have told me in great detail. Because she’s been picturing it and looking forward to it. She loves you so much, Harry. But whenever I ask you, or Mum does, you kind of avoid it. And I think that you don’t think about it so much, do you? You aren’t picturing your life together.’

There’s silence.

‘Are you, Harry?’

There’s more silence. I let it fill the room. It’s very unusual for Harry’s room to be silent, but he needs a bit of thinking time.

He looks angry, and then frightened, and then sad. He comes over and sits beside me, but doesn’t look at me. He plays with a frayed thread on the knee of his jeans.

‘I try. But then I just picture myself on a beach somewhere. By myself. Escaping. How did you know?’

‘Because I care about you,’ I say. ‘Because I’m your sister. Because I know when something’s not right. I think Crow knew too. She could never get the dress to work.’

Harry gives a short laugh. There’s a pause. Then he says, ‘When I proposed to Issy, it felt so right. It just happened. She was as surprised as I was. She’s so beautiful, Nonie. Inside too. She’s such a perfect, perfect girl.’

I nod. Having checked Isabelle out, I agree. She is perfect. The only trouble is, perfect isn’t always perfect.

‘I just pictured us carrying on like we were, but, you know, for ever,’ Harry says. He shakes his head, cross with himself. ‘It seemed a good idea at the time. But then the wedding thing got bigger and bigger. And we started talking about kids, or at least, Issy did. Then she saw my face and backed off and suggested a puppy. At least to start with. I felt guilty enough about that.’

He looks at me helplessly. He’s obviously not proud of himself, but he’s lost.

‘You’re only twenty-four,’ I say.

‘She’s twenty-one. But she knows exactly what she wants. And she means it. Why shouldn’t I?’

I shrug. ‘Not everyone’s as grown-up as Isabelle inside,’ I suggest. ‘But you’ve got to tell her. You know that, don’t you? Before you totally break her heart.’

He jumps up and starts shoving more stuff in his suitcase.

‘That’s the problem. Don’t you see? I’ve been thinking about it for months. I can’t let her down now. It really would break her heart. And I couldn’t bear that. She doesn’t deserve it.’

He catches my eye. It is the eye of a sister who knows him, and knows the right thing to do. I don’t say anything, but he flinches anyway.

‘You can see that, can’t you, sis?’

I get up and head for the door. I pause there for a moment, with my hand on the handle.

‘One day she’ll work it out,’ I say. ‘The way I did. How will she feel then?’

He crumples, as if I’ve hit him with a cricket bat. I let myself out of his room as quietly as I can. Back in my own room, I call Liam, who reassures me, yet again, that it was the right thing to do.

It doesn’t feel like it, though. Normally, when you do the right thing you feel great afterwards. A real sense of achievement. I just feel empty and miserable. If only I were doing a paper on Shakespeare’s tragedies tomorrow, I’d be in the perfect mood to write it. Unfortunately, it’s Business Studies. Yaaay.

‘He didn’t?’

Yesterday, Mum was on the phone to Granny, sobbing. Today Granny is in our kitchen. Mum is still sobbing, but face to face this time.

‘He did. He told me two nights ago, from Milan.’

‘Why?’ Granny wails. ‘She’s the best chance he’ll ever get!’

‘He says he doesn’t love her.’

‘Doesn’t love her? The boy’s besotted.’

‘That’s the thing,’ Mum says in a bit of a break between sobs. ‘Besotted, not in love. Not long-term love, anyway. That’s what he said.’

‘Idiot,’ Granny says crossly, getting a hankie out and handing it to Mum. ‘He doesn’t know what he’s talking about. I bet she took it badly.’

This doesn’t help Mum, who nods and goes back to sobbing. ‘She’s inconsolable, apparently. She’s had to pull out of several shows. The poor girl.’

‘And why now?’ Granny asks angrily. ‘Why suddenly now, for God’s sake?’

Mum looks up helplessly and shrugs. I’ve been watching through the doorway and decide to make myself scarce. Unfortunately, it’s hard to make a secret getaway in Doc Martens and Granny calls me back.

‘Nonie! Tell me you didn’t have anything to do with this.’

Lie, I tell myself. Just lie. You know you can do it. You do it all the time. Lie your little tartan socks off. But Granny is staring at me with a particular stare that only Granny can do.

‘I might have mentioned I was worried about him,’ I say.

Mum looks up, shocked. Granny looks absolutely furious. The next fifteen minutes are not remotely funny. By the time it’s over, I just about have the energy to creep upstairs to my room and text Liam a sad face, before curling myself up into a ball on the bed.

He calls back instantly. I uncurl myself enough to pick up the phone from where I’d dropped it on the floor. Then I curl myself up again.

‘What’s happened?’ he asks. ‘Nothing to do with your mad granny, by any chance?’

I tell him about the conversation.

‘So they’re saying it’s your fault?’ he asks.

I think back over the past quarter of an hour. And yes, that pretty much seems to sum it up.

‘But you were just trying to stop Harry making a world-class mistake.’

‘According to Granny, I was selfishly trying to stop Harry being happy so I could get to stay in my own precious bedroom. Mum looked extra shocked at that.’

‘Hey – if he really loved Isabelle, he’d have just told you not to be so stupid. He wouldn’t have called it off just so you can keep your room.’

I sigh. It’s fine for Liam to be telling me this. I just wish he could have been there to tell Granny. I’d have liked to see him try.

‘Sorry,’ he says. He realises he’s not being very helpful. ‘They’ll come round.’

‘Sure.’

‘Nonie?’

He can tell there’s something else. Something I’m not saying. Something that’s even worse.

I hesitate. Until a few weeks ago, I wouldn’t have told anybody the next bit, but things have changed. Some of them for the better. Including being able to tell Liam anything and know that I can trust him.

‘It was after I left. I was on my way up here, but I kind of stopped on the stairs . . . And I heard what Granny said to Mum.’

‘Which was?’

I pause. I try and do Granny’s voice and make a joke of it, but it comes out all cracked and wrong. ‘“Well, that’s the second family marriage that girl’s managed to ruin. What next?”’

‘You’re joking! Your granny said that?’ he asks. He’s shocked, which is comforting.

‘Well, she’s right,’ I say. ‘And I told myself I wouldn’t do it. I told myself I’d be good.’

‘You are good, Nonie,’ he insists. ‘God, I wish I could be there with you. You haven’t talked to your mum yet, have you?’

I shake my head. He can’t see that over the phone, but I’m not really thinking straight.

‘Talk to her,’ he says very slowly, like I’m a little child, or a tourist asking for directions. ‘Talk to her soon. This is getting ridiculous.’

I promise, once again, that I will talk to Mum. Liam knows I’m lying by now, but there’s not much he can do about it over the phone. Besides, now would be a really, really stupid time to bring up the whole subject of Dad and affairs and mistakes and wasted relationships. I can hear raised voices downstairs and Mum sounding distinctly upset. Even Granny can’t calm her down. The last thing she needs is me going on about family history.

When I eventually go back downstairs, the house is silent. Granny has gone and Mum’s out too. She’s left me a note, just saying she’ll be back later. I feel as if I’ve pushed them all away and I’m starting to wonder if I wouldn’t be better off in a rented room somewhere, with Mum safely in Rio and me out of upsetting range for a change. Liam said the whole thing’s ridiculous and he’s probably right. It probably does look ridiculous from a distance. But from right in the middle, it feels as lonely as I can possibly imagine.