‘Oh, yes. Well that’s subjective age, Bertie. It depends on how you feel and think inside you. So you may be twenty, but not feel twenty. Sometimes there are such people. People who don’t grow up, for example.’

‘Like Peter Pan?’ asked Bertie.

Irene shook her head. ‘Peter Pan? Oh no, Bertie. Peter Pan was a projection of J. M. Barrie’s fantasy, Bertie. He was a wish fulfilment. Peter Pan would have loved to grow up, but he wasn’t allowed to by Barrie. And that’s because Barrie wanted to regress to that age himself. That’s where he was stuck.’

Bertie looked concerned. ‘Can you get stuck, Mummy?’

‘Yes, you can, Bertie. Lots of people are stuck.’

‘Even in Edinburgh?’ asked Bertie.

‘Even in Edinburgh, Bertie. Edinburgh is full of people who are stuck. Most of them don’t realise it, of course, but they’re stuck all right.’

‘Are you stuck, Mummy?’

Irene laughed. ‘Certainly not, Bertie. I assure you – I am far from being stuck!’

‘And Ulysses? And Daddy? Are they stuck?’

Again Irene laughed, but less spontaneously, perhaps. ‘Ulysses is currently at the oral stage, Bertie. You may have noticed that he sucks everything he can find. He wants to eat everything up, you see. That’s perfectly normal. As long as he moves on, which I am sure he will. And as for Daddy, of course …’ She faltered. Stuart was clearly stuck, but she did not feel that she could explain that to Bertie.

Poor Stuart, she thought. Stuck in that dreadful office in the Scottish Government. Stuck with all those other statisticians conjuring up figures for ministers who were themselves stuck. It hardly bore thinking about.

‘Is Daddy stuck?’ persisted Bertie.

‘No, of course not. Daddy is entirely … You mustn’t worry about Daddy, Bertie. Daddy is fine … in his own way.’

Bertie looked relieved. ‘But I still think it might be better to do something else,’ he said. ‘What about Italian? There’s always Valvona & Crolla …’

‘We aren’t going there just now, Bertie. And there are better ways of practising your Italian than reading the labels of packets of pasta and tins of goodness knows what. No, Bertie, we have an appointment with Dr St Clair, and we must keep it. That’s all there is to it.’

Bertie looked down at the pavement, making sure that he did not tread on any of the lines. Tofu had said that somebody had been lost in Edinburgh only the week before because he trod on the lines. The police were looking into it, he said, but they had been able to come up with nothing. All they found, said Tofu, was his shoes.