But there was. A little girl called Jessica. All my life, without knowing it, I’ve had a sister, growing up miles away, with no idea I existed either.

And today, at last, I’m going to meet her!

Just the thought makes me feel exhilarated and jumpy all at once. How will we be the same? How will we be different? What will her voice be like? What will her clothes be like?

“Do I look OK?” I ask Luke, while anxiously surveying my appearance in the mirror. We’re in my old bedroom at my parents’ house, and I’m putting the finishing touches to my meeting-my-long-lost-sister outfit. It’s taken me several days, but after a lot of thought I’ve decided on my most flattering Seven jeans, some boots with spiky heels, a gorgeous pale pink Marc Jacobs jacket, and a T-shirt made ages ago for me by Danny.

“You look great,” Luke says patiently.

“It’s like… balancing formal with informal,” I explain. “So the jacket says ‘This is a special occasion,’ whereas the jeans say, ‘We’re sisters, we can be relaxed with each other!’ And the T-shirt says…”

I pause. Actually, I’m not sure what the T-shirt says, apart from “I’m friends with Danny Kovitz.” And I’m not even sure how true that is anymore. He hasn’t called back, even though I’ve left two messages.

“Becky,” says Luke, “I don’t honestly think it matters what you wear.”

“What?” I wheel round in disbelief. “Of course it matters! This is one of the most important moments of my life! I’ll always remember what I was wearing the day I met my sister for the first time. I mean… you remember what you were wearing when you met me for the first time, don’t you?”

Luke looks blank.

He doesn’t remember? How can he not remember?

“Well, I remember,” I say crossly. “You were wearing a gray suit and a white shirt and a dark green Hermès tie. And I was wearing my short black skirt and my suede boots and that awful white top which made my arms look fat.”

“If you say so.” Luke raises his eyebrows.

I smooth down my T-shirt. “I just want to look right. Like a sister.”

“What do sisters look like?” Luke asks, looking amused.

“They look… fun!” I think for a moment. “And friendly. And supportive. And like they’ll tell you if your bra strap is showing.”

“Then you do look exactly like a sister.” Luke kisses me. “Becky, relax! It’s going to be fine!”

I know I’m a bit wound-up, but I just can’t get over the idea of having a sister after being an only child for so long.

Not that I’ve minded being on my own or anything. Mum and Dad and I have always had a great time together. But sometimes I’ve heard other people talking about their brothers and sisters and wondered what it was like. I never thought I would actually get to find out!

What’s really spooky is that all this week, I’ve suddenly been noticing sisters. They’re everywhere! For example, the film of Little Women was on telly the other afternoon — and right after was a program about the Beverley Sisters! And every time I’ve seen two women together in the street, instead of just noticing what they were wearing, I’ve thought, “Are they sisters?”

It’s like there’s a whole world of sisters out there and finally I’m part of it.

I feel a smarting in my eyes and blink hard. It’s ridiculous, but ever since I heard about Jessica, my emotions have been all over the place. Last night I was reading this brilliant book called Long-Lost Sisters: The Love They Never Knew They Had and tears were streaming down my cheeks! The stories were just amazing. One was about these three Russian sisters who were in the same concentration camp during the war but didn’t know it. Then there was this woman who was told her sister had been killed but she would never believe it, and then she got cancer and there was no one to look after her three children, but they found the sister alive, just in time for them to say goodbye…

Oh God, I’m going to cry just thinking about it.

I take a deep breath and wander over to the table where I’ve put my present for Jessica. It’s a big basket full of Origins bath stuff, plus some chocolates, plus a little photo album of pictures of me when I was little.

I also got her a silver bean necklace from Tiffany, which exactly matches mine, but Luke said it might be a bit overwhelming, presenting her with jewelry on our first meeting. Which I didn’t really understand. I mean, I’d love it if someone gave me a Tiffany necklace! But he was really insistent, so I said I’d keep it for later.