She has spent most of the day reading and is feeling rather out of touch with reality, as if her own life has become insubstantial in the face of the fiction she's been absorbed in.

For a while I used to listen to those whispers about babies costing you books, and Cyril Connolly's loathsome quote that "There is no more somber enemy of good art than the pram in the hall." But it's rubbish. Absolute rubbish. A huge amount of your work is done when you're not at your desk. Knotty problems that you need your unconscious to solve. So it can be helpful to walk away and focus on other things and it can be helpful to be a bit harassed in your daily life, to be hungry for time to write.

We always planned to move back to the Republic but it never happened, I'm not sure why. My dad is one of those immigrants who never leaves the place he came from. He talks about Ireland all the time. If any Irishman wins at any sort of sport, he sees it as a personal achievement.

I try not to be too precious about my writing, and I try to be willing to walk away from it for a few hours when something's not working, to let things percolate a bit. I try not to hide myself away from life too much, because I think that's a risky thing for a writer to do.

I think all families have these secrets, and it's sometimes the strangest things that bring them out. That was part of my interest in the heatwave, in heat as a catalyst for uncovering truths. I was reading Alice in Wonderland to one of my kids recently, and I remembered that it starts on a really hot day. Alice falls asleep because of the heat; the whole story is predicated on falling into a heat-fueled dream.

We all have a family, whether we like it or not; we all come from somewhere, and there's something strange in the way you have, with siblings, two or three personalities yoked together for life. You grow up thinking those family relationships are set in stone and then you get older and realize they're not. They're always shifting.

In the course of writing a book I'll produce loads of pieces of paper to help the novel itself. Diagrams, charts, family trees. And at the end of each book I'll pack it all away. It takes me a while to do it - it's like a relationship that way; there's a period of letting - go, of grief, in a way - but then I box it up, label it, and put it in the attic.