All I can manage is, ‘You knew?’

‘I was at university with him, remember?’ Dad says. ‘He wasn’t out, to use today’s term. But you know what it’s like at college. No one had secrets. He had a fling with a lad from my corridor, who also eventually got married and went on to be a professor of history at Harvard. I shouldn’t tell you this, but when I was very drunk one night I actually necked with him at a party.’

Dad! Too much information!

‘It’s all right,’ Dad assures me. ‘It was before I met your mother and she knows all about it. She thinks it’s terribly funny. But what on earth made you think there was anything between him and Clare?’

The moment of levity has passed. The oppressive sadness is back.

‘It’s complicated. I was told Clare had a fearful public row with Kendall, and then I heard he was having an affair with one of his staff. I added two and two, and got five.’

I consider telling him about Clare’s pregnancy. That would really smash down the barriers between us, but it would be devastating for him and Mum. I decide against.

‘There was a tax policy Clare had been working on, something she really believed in, that she thought would help raise important sums to invest in public services. Kendall was championing it, but then he reversed and axed it. Clare was furious, and did something I would never have expected of her: she called him “fucking corrupt” in front of his officials.’

Another pause. When he’s thinking, the wait is nerve-wracking. And it’s normally a precursor to proving I’m a fool.

‘This policy you’re talking about, I assume you mean her idea that the Treasury could raise billions of pounds by abolishing the exemption of pension funds from paying tax on the dividends they receive?’

I’ve wrapped the phone cord around my index finger so tight it’s left a welt. ‘You knew about that?’

‘When your sister was working on something thorny, she would often chew it over with me.’ Immediately I feel another emotion, jealousy – though I am not sure whether I am jealous of Clare, for having Dad’s attention, or Dad, for having such a mutually trusting relationship with Clare. I’m left feeling an outsider in my own family again.

‘Did she give you any clues as to why Kendall canned it?’

‘She said he’d capitulated to pressure. I think the expression she used was “nobbled”. As far as I could gather, a business that’s very important to the government would have been in dire straits if its pension fund had lost all those tax credits. In some way or other, billions of pounds were at stake. This business somehow twisted the Chancellor’s arm.’

‘Billions of pounds were at stake? For one business? She said that?’

‘Yes.’