‘Of course we love you both,’ she replied from behind the curtain. ‘But that doesn’t make parenting any easier on a relationship. I gave up a lot for our family, Ros. I didn’t tell you at the time but I was up for a spot at Oxford when Jo came along.’

I guessed that this was the wrong time to suggest she should have known what caused pregnancy by the time she was forty-two. There really was no excuse for it, we had five TV channels and a satellite dish by then.

‘And what did your dad give up? Nothing. Most of my friends were celebrating their kids moving out and getting their lives back and there I was, being forced out of a job I loved to stay at home with a stroppy teenager and a gifted toddler, while your dad went mincing off around Europe on an awful lot of business trips.’

A horrible thought crossed my mind that I couldn’t keep off my face.

‘I do remember him going away a lot,’ I said, putting two and two together and coming up with a number I didn’t like the look of at all.

‘Everything is fine between me and your dad now but it wasn’t always. Back then everyone just assumed I’d give up my career to look after you girls while your dad kept doing whatever he wanted.’

‘You’re talking like it was a million years ago,’ I mumbled. ‘Jo’s only eighteen.’

‘Exactly,’ she said, emerging in her usual Prince of Wales checked trousers and a black silk shirt I would never again take for granted as long as I lived. ‘And don’t you forget it. As soon as we make an inch of progress, we write off yesterday as though it were ancient history. We’d all do a good deal better to remember what happened yesterday. It was this millennium, not the dark ages, and I was passed over for a job I was more than qualified for and was as good as promised, all because I went in to interview with a room full of men when I was six months pregnant. We tend to assume we’re entitled to the things we have, we rewrite history to make life easier for ourselves. It’s not the case, Ros.’

‘I know, Mum,’ I said quietly.

‘Your dad tried but he was never very good at the hands-on parenting,’ she said, straightening her hair in the big mirror. ‘And as much as he loves her, he never really knew what to do with your sister. She’s always been a handful.’

‘I knew it was Jo’s fault,’ I whispered into my coffee.