I had looked at his boots through a louvre from nine inches off the floor and I knew the exact board — there is a chestnut floorboard on that landing with a shake in it that my father filled in 1998 and that I have known my entire adult life — and for about two months I could not walk over that board without my heart going.

I did four things about the house and one of them was ridiculous and turned out to matter most.

I changed every lock in the building in the first week and put a proper monitored system in, which is obvious.

I had the electrical panel replaced, which was overdue by about eleven years and which I did partly for the wiring and mostly because I could not look at that box.

I moved my bedroom.