Next to Ned Bryanston is a shrunken figure with powdery wrinkles and a black spidery hat atop her white hair, which has been spun into a special helmet for the occasion, and piercing blue eyes. Celia is, I notice, looking ancient, but then people one doesn’t see for a year or two, or even just a few months, so often do. Especially at parties. In the pew behind Lulu and Ned and Celia, Jesse Marlon, and Judith and her civil partner, Kit, and their daughter, Jeremy, who have made the trip over from the Catskills, are sitting in a marvellous display of the limitless possibilities for lasting emotional trauma posed by the blended or recomposed family, a flawed but modern institution whose obvious, inherent limitations such occasions can test to the hilt.

Sir Michael and Lady Hutton, who are devoted to Celia, are in front of them, occasionally turning to see if Celia is all right and to frown at Lulu, who is texting into her mobile.

So all of us are seated in the cramped mahogany pews, inhaling the heady scent of the flowers, the dust of old hymnbooks and the stale must of embroidered prayer-cushions, ever more eagerly awaiting the moment when the organist will strike up the chords of ‘Here Comes the Bride’, and we’ll finally clap eyes on the radiant vision of Serena.

Five minutes of hush pass. Ten minutes. Twenty. It is now twenty minutes past the anticipated hour. Ralph keeps telling me how long we’ve been sitting here, as if he is doing the timechecks on the Today programme.

‘We must have been here forty-five minutes now,’ he says without expression.

Colin Watts is beginning to look abject and young, even from the back, and the altar is beginning to take on the air of an Aztec chacmool, as if ready to receive the blood offerings culled from the youngest and strongest of the tribe to appease the great sun-god.

I am staring straight ahead, annoyed that I have already cried once (I made the terrible mistake of reading the honour roll of names and ages of the young men of this church and parish, beautifully inscribed in gothic gold on dark wood, who gave their lives in the Great War) and the service hasn’t even started yet. Any occasion perfumed with emotion – be it a special assembly at school, a father–son cricket match, anything to do with the Queen, veterans in uniform, children’s hospices, causes me to well up. I seem to be crying constantly these days.

I am wondering what could possibly have happened to make Serena so late on the biggest day of her life so far.

By now even Cath, who does everything with such admirable, snapping zip-de-doo, is looking anxious.