She answers under her breath, “At least two-to-one, I should think, with Stella around.”

Well . . . it is Stella’s fault that the upstairs has flooded. I don’t know exactly what happened, but she’s been making her sculptures in the bathroom ever since Dad banned them from the kitchen, and something went badly wrong this afternoon when she clogged the U-bend of the basin with clay and then tried to unclog it with a screwdriver. Credit where credit’s due, though: just as stress levels ought to be rocketing—what with our sitting room full of guests, and water dripping through the ceiling onto the sitting-room carpet, and the cheapest plumber in the phone book charging £150 an hour—it’s thanks to Stella that the atmosphere lifts.

“Freya!” she cries, bursting into the sitting room with a bucket for the drip in one hand and a box of deluxe Christmas crackers in the other. “Look what I’ve found. We forgot to pull the crackers on Christmas Day!”

Before we know it, we’re all donning paper crowns, Aunty May is telling fortunes with a cellophane fish, and John from three doors down is failing to get his head round a joke. “Question: What cheese is made backward? Answer: Edam.” Stella turns ABBA up to cover the noise of the drip, and then she climbs onto the sofa, glass in hand, and bounces from foot to foot as she sings along to “Fernando.”

Stella is astonishing in her cheap, shimmery dress. She is like a fire: everyone’s instinct is to draw near and stare. Even the plumber pauses in the doorway, on his way upstairs to the bathroom. Even Dad—who has more reason than anyone to feel annoyed—seems to soften when he looks at her. As for Tom—I don’t wish to downplay the suffering he’s gone through with his broken marriage, but I can’t help suspecting there’s a guilty corner of his mind that’s glad to be free.

I call it a New Year’s Eve party, but it’s pretty low-key. Apart from the three of us, there are only six guests: a couple of neighbours, one of my school friends, Zoë from Dad’s office, Aunty May, and—of course—Tom. Stella hasn’t invited any of her own friends, although she’s been checking her phone all evening, smirking every time it pings.