I understand women in a way Millie never has. Stacey’s a minor celebrity used to being the centre of attention in any gathering. The women she meets outside work will either fawn all over her, or resent her for being famous and wait for the right moment to slide a knife between her ribs.

The simplest way to make a woman like Stacey feel secure is to remove the element of competition. Counterintuitively that doesn’t mean fading into the background.

People like beauty. In art, in nature, in architecture. In each other.

Ideas of beauty may change from one era or one culture to another – the curvy Fifties followed by the twiggy Sixties – but there are certain elements that remain the same. Symmetry. Proportion. Scientists have even come up with an actual measure of physical perfection: the golden ratio, which originates from the European Renaissance and is based upon the ancient Greeks’ measure of perfect beauty. We find it when we divide a line into two parts so that the long part divided by the short part is also equal to the whole length divided by the long part. You don’t need to know this, but the golden ratio is an irrational number that approximates to 1.6.

You don’t have to be a mathematician to appreciate its importance, either. You recognise it instinctively a dozen times a day without even being aware of it. While you’re looking at someone’s face, and returning their smile, your subconscious is busy measuring: the length of the face, divided by the width.

All of which means Millie has a natural born advantage. Not using it would be like turning up with a knife to a gunfight.

My wife has no idea quite how beautiful she is. She makes the most of her genetic lot through exercise and hard work, but there’s no vanity involved. When she looks in the mirror, she doesn’t see the beguiling woman I see.

She sees her mother.

Millie rarely capitalises on her appearance. She seldom wears make-up and lives in jeans or work scrubs: I can’t remember the last time I even saw her in a skirt. But I persuaded her to make an effort for Stacey Porter. And Stacey told herself a woman who looks like my wife doesn’t need to feel jealous or resentful of her success. Millie’s appearance lifts her out of the ranks of civilian non-celebrities and puts her on Stacey’s level, giving her a passport to her world.

I went to all this trouble so she’d see Millie as a worthy successor to the Glass House: so she’d want her to live in it.