A hushed silence had fallen, and Sabrina was opening her mouth to sing her legendary solo, eyeing her murmuring sister furiously. It wasn't that she couldn't sing, but why was she singing on her own? If a solo was called for, why not a child? And her voice had that terrible shaky vibrato so that "Heavenly peaaace . . ." seemed to go on forever. Babs lit a cigarette, which struck me as unbearably funny, and every time she exhaled, it was with a bored, exhausted breath. I stared at the Persian carpet, knowing my only hope was to think hard about global warming or the economic deficit, but my shoulders were beginning to shake. Every time Sabrina hit a high note, Babs exhaled more wearily, and when she'd finally finished I had tears streaming down my face. I wiped them carefully with one finger before I looked up, but when I did, it was straight into Hugo's highly amused eyes on the other side of the tree. He was grinning with delight at my predicament, absolutely beaming, and refusing to look away, even when I pretended to study my hymn sheet for the next carol. When I looked up, there he was again.

"You were in serious trouble," he told me later, when we were indeed supping mulled wine and having a cheeky smoke on a freezing little bench on the terrace outside.

"I'm afraid Babs has that effect on me. She's just the naughtiest girl in the school."

He didn't say anything and I realized what an incredibly crass thing I'd said.

“It's OK," he said, seeing me suddenly confused and tongue-tied. "I'm totally used to it. And actually, it's a relief to talk about it. Etta doesn't feel that way, but I do. I'd rather it was out there. Can't bear everyone privately thinking, I wonder how those kids feel about it."

I glanced up at him, my face asking the question.

"I don't," he said truthfully. "I mean — really think about it. And it would be cruel to say Mum brought it on herself, but Dad had a chat with me when he realized I knew. Apparently Mum shut up shop almost immediately after I was born."

Half of me couldn't believe I was having such a grownup conversation, the sort you might have after a year of going out with someone, and half of me was riveted.

"But why? Isn't that just asking for trouble?"

"Exactly. What was Dad supposed to do?"

"Of course, you've only got his word for that," I reminded him.

"Except they have separate bedrooms. Have done ever since I can remember."

“Oh.” I thought back to my own parents, with their tiny double bed, the laughter reaching right to my room down the hall.

“Mum has insomnia, apparently, and Dad snores and likes a really hard mattress — that's the party line. But still."