"Really?" I said. "Are you sure? Aren't you going out?"
"No," she said, puzzled.
Teenagers these days seem to go out all nights of the week. I don't think Saturday nights have the starry allure they had in my day.
So off we went. She drove us beautifully down pitch-dark country lanes.
"How late can we be?" said my friend.
"No later than midnight," said her daughter firmly.
For some reason, this stern curfew made us feel like teenagers ourselves. Well, that's my excuse anyway.
It's possible, looking back, that we might have had a glass too many. Certainly, by the time we all piled back into the car, we were finding everything hysterically funny. Even when it wasn't.
The phone rang. It was my own teenage daughter. "Where are you?" she said.
"On our way," I said airily.
"You sound funny," she said.
"And you're much later than you said you'd be."
"Sorry," I said in a small voice.
In the morning, I woke with a slight headache. Stumbling down to the kitchen in search of a painkiller, I found my daughter sitting at the kitchen table. She raised an eyebrow.
"I think I'm coming down with something," I said. She just looked at me.
"There are so many things going round this time of year," I said. "It's what happens before Christmas. Colds. Flu. Winter bugs."
"You'd have thought," she said, in a slightly bored voice, turning back to her copy of You magazine, "that you'd know better by now."
Oh, the shame.