“Okay,” said Sophie.

“And no helping yourself to any of my clothes while you’re at it, either.”

“I wouldn’t help myself to your clothes,” said Sophie, “if—”

“No jokes, Sophie.”

“Sorry,” said Sophie.

“It’s just so embarrassing,” said Lulu a few days later, sprawling at the scrubbed hardwood table in Emma and Matthew’s small, immaculate kitchen: Emma took pride in keeping her surroundings tidy. It was Tuesday evening, when Matthew played squash with his friend Cheng, and Lulu had acquired the habit of dropping into the flat for a sisterly visit. “Charlie says she doesn’t mind, but I’m sure she does really, and even if she doesn’t mind now, I know she will one day, because in the end you do, don’t you? I’ve minded about Sophie ever since she was two.”

“Charlie was the one who invited her, though, wasn’t she?” Standing at the stove, Emma poked gently at the vegetables in the pan and turned her head to peer at the pasta bubbling in the pot beside it. “I was there, remember, I heard her.”

“Yes, but she didn’t know what she was taking on! We know what it’s like to live with Sophie, but she doesn’t. Didn’t, anyway—I’ve a horrible feeling she’s starting to find out.”

“And you tried to warn her about that, too, and she went ahead anyway. I wouldn’t worry about it too much, Lulu. Charlie can take care of herself, and you know Sophie—everyone ends up loving her anyway. And it’s not as if she’s going to attack you in your sleep with a machete.”

Despite herself, Lulu produced a smile.

“Not on purpose, anyway,” she commented.

“Sorry!” Emma widened her eyes, slipping with ease born of long practice into their Sophie imitation. “‘Oh, Lulu, was that your leg? I’m soooo sorry, I didn’t mean to, but never mind, you’ve still got the other, whoops, no, you haven’t, oh, and there goes your head, too, I’ve killed you! Mom! Charlie! Emma, you’ll never guess what’s happened!’”

“Well, if she ever does, feel free to kill her back on my behalf.” Lulu reached across the table to pull towards herself a large book with a picture of a young woman in white on the cover.

“What’s this?” she asked.

“It’s a book,” Emma told her.

“I can see that. How to Plan the Perfect Wedding.” she looked at it, frowning. Like many people who are academically gifted, Lulu had a tendency to overlook the more mundane details of the practical world around her; although she knew quite well that Emma and Matthew were planning to get married, it had not seriously occurred to her until now that this would involve having a wedding. “Do they have books about that?” she asked.

“Apparently,” said Emma.

“Hmm.” Lulu opened the book and flicked through its pages, staring at pictures of roses, and shining gold rings, and tables set with crisp white linen. “Are you really going to do it?” she asked then.

“No, Lulu.” Well used by now to her sister’s scattershot grasp of social customs, Emma shook her head sadly as she hooked out a piece of pasta to taste for texture. “We’re not really going to get married, Matthew and me. That announcement we made to the family a few weeks ago, and this ring I’ve been wearing ever since, were all part of a cunningly devised master plan to get Dad to open the good champagne. Of course I’m going to do it—what a weird question. Truly, even for you, that is seriously a weird thing to ask.”