I knew she thought I’d forgotten all about it. On the morning of her birthday, I got up half an hour early – well before her throat-clearing operation – and put a bunch of pink roses outside her bedroom door. I’d bought them the day before, and kept them in a jug of water in my wardrobe so she wouldn’t see.

I got back into bed. Half an hour later, I heard the floorboards creak. Then a crash, a stumble, and a yelp of surprise. Phyllis had kicked over the roses by accident and they were all strewn about the floor, but I could see she was pleased. She kept saying ‘Oh my goodness’ as she collected them up in her nightie.

I took her out for dinner later on, to a French restaurant in town. She put on her best blouse, with a fussy wee frill at the neck, and her pearl earrings, and a daub of blue eyeshadow to set off the rose-tinted lipstick. When I saw her appear like that at the bottom of the stairs, all done up to go out, I felt an awkward pang of love for her.

In the restaurant, she had a couple of glasses of white wine with her dinner, and got a bit tipsy. The conversation got on to Mary and Sam’s holiday: they had gone to Tenerife.

‘It’s good for them to go somewhere on their own without me,’ she said. ‘I sometimes felt as though I was a bit of a spare part.’

I said nothing, sawing away at my steak. I could sense the faint electricity of something meaningful approaching.

‘I mean, I wouldn’t have wanted Mary along all the time when I was going out with my boyfriend,’ she said. There was a second’s hesitation before the word ‘boyfriend’, as though she had doubts about whether to mention it, but had ploughed ahead anyway.

I had never heard Phyllis talk about a boyfriend before. I couldn’t imagine Phyllis with a boyfriend. Mary had always said that Phyllis was too delicate to get married. I carried on cutting my steak without showing surprise, so as not to scare the revelation away.

‘When were you going out with him, Phyllis?’ I asked.

‘When I was nineteen,’ she said, ‘He was a medical student. We used to go out to dances together. Mary didn’t like him. She said he was sly but he wasn’t, he was just shy of her because she tried to bully him with too many questions.’

She smiled suddenly. ‘He used to call her the Iron Lung, because she was always hunting after me, shouting my name.’

‘How long did you go out together?’

‘Two years. Your mother liked him. The pair of us used to give Mary the slip sometimes and go out to the dances together.’