I caught a glimpse of Evelyn and Cassie. Evelyn was stooping right down, so that her spine curved to show the lovely long chain of bone, and her slender wrists crossed to hold Cassie’s hands. They were twirling in dizzy circles and Cassie’s head was thrown right back in the last transports of exhausted delight. I turned away again to talk and dance some more. A few minutes later I heard Cassie screaming. The sound was only just audible over the thump of music but I heard it as clearly as if the room were silent and deserted.

Frantically I pushed my way to the spot where I had last seen her. She was lying on the floor, her face mottled and her heels drumming. Relief brought my breath back. It was nothing more than a temper tantrum brought on by tiredness. Evelyn was stooped over her, and Penny was crouching beside Evelyn and trying to get past her to Cassie.

‘What?’ I asked Penny over the noise of Jerry’s Desmond Dekker tribute number.

‘She’s tired. Not surprisingly.’

Evelyn was shouting at Cassie and pulling her upright. A clearing had opened around us in the crowd but otherwise no one was paying much attention. Jerry at the mike had his eyes closed.

‘No,’ Cassie screamed and drummed her heels even harder.

Penny was trying to stop Evelyn hauling on Cassie. The two of them were facing each other off and when Cassie briefly opened her eyes to check what was going on she immediately saw it and screamed harder. Penny locked her arms round Evelyn who let go of Cassie to try to fend her off.

Seeing my chance, I stepped in and scooped the child up. Her body was rigid. ‘Cassie! Cassie, it’s all right, you’re all right. Come to Sadie-lady.’

She took a deep breath to go on yelling but then thought better of it. She went limp and heavy in my arms.

‘What are you doing?’ Evelyn demanded, but not very aggressively. We were all pleased the tantrum had blown itself out. Penny’s eyes met mine imploringly.

‘I’ll take her for a few minutes,’ I said. ‘You two go and, you know, have a dance. Enjoy the party. Cassie will be fine with me.’

Penny’s arms were still round Evelyn. She murmured in her ear and stroked the waves of hair back from her cheek. Evelyn nodded, pouting a little, and let her head fall on Penny’s shoulder.

I carried Cassie away towards a door at the side of the room. There was a green EXIT sign above it. As I made my way I saw that Mr Rainbird, resting for a few bars, was watching me go.