David Milford Haven had told her all about it on Boxing Day when he had come to say goodbye. He had been drinking all evening and was swaying slightly, his eyes unfocused.

‘Hélène is really special to Philip,’ he had said, slurring his words. ‘They’ve known each other since they were children. She’s a great girl.’

It had been a salutary reminder to Elizabeth that there were other people in Philip’s life, including ‘great girls’ who knew him really well. She was jealous of the unknown Hélène, she realised, testing out the feeling. She couldn’t remember ever feeling jealous before – why would she? – but Elizabeth recognised its pinch straight away.

The fact that she knew that it was irrational and unfair only made the pinch sharper. Philip had not forsworn other friendships, other love affairs. They had agreed to write, that was all.

Once, when she and Margaret were quite small, before Papa became King, Crawfie had taken them for swimming lessons with Miss Daly at the Bath Club. The first day they had both been apprehensive and had clung to Crawfie’s hands. There had been a girl standing on the highest board, poised to dive. Elizabeth can still remember the echoing shouts, the mingled smell of chlorine and damp wood, remembers gasping as Miss Daly gave the word, and the girl bounced on the board and executed a perfect swan dive into the pool.

‘I shall never be able to do that,’ she had said, awed at the girl’s bravery.

‘Oh yes, you will,’ Miss Daly had said with a laugh. ‘That girl is blind, so if she can do it, you certainly can.’

Elizabeth often thought about what it must have been like for that girl to climb up the steps and walk along the board without being able to see what she was doing. Had imagined the bravery of taking the leap into the unknown. Meeting Philip again that Christmas felt in an obscure way as if she were walking carefully along a high board and getting ready to dive, but when she heard about Hélène, she lost her nerve. She crept back along the board to safety and climbed back down to the ground.

She hadn’t given up, just as she hadn’t stopped asking to join the ATS, but she had protected herself. She would not be too warm with Philip, she had decided. She would not make a fool of herself. She had her pride, after all.

It has been good to write, though. Elizabeth feels as if she knows Philip better now and she longs to see him again.

And now the war is over.

Yesterday, Churchill announced victory from the balcony of the Ministry of Health in Whitehall. Elizabeth and Margaret leant close to the wireless to hear him speak to the crowd that had gathered in anticipation of the news they had been waiting for. ‘This is your victory!’ he declared and the crowd roared back as one: ‘No, it’s yours!’

Elizabeth’s throat had snapped shut when she heard that. What would they all have done without Churchill?

‘It is the victory of the cause of freedom in every land,’ Churchill went on in his gravelly voice. In all our long history we have never seen a greater day than this. Everyone, man or woman, has done their best.’

Elizabeth can’t help feeling as if her best has not been very much. It is barely a month since she joined the ATS. She has been hoping to join the headquarters as a junior officer to work on transportation, but Papa is already making noises about needing her at home to help him with royal duties.

Duty. The one word Elizabeth cannot turn her back on.

She holds the thought of Philip close to her, and she treasures his letters. He wrote and asked her to send him a photograph so that he could look at her while he was reading her letters to him. It felt almost like a declaration. A photograph means more than a letter. She spent ages choosing one to post out to him.

In return, as requested, he sent her a photo of himself looking coolly handsome in his naval uniform. Elizabeth put it on the mantelpiece in her sitting room where she could see it every day until Crawfie clucked and told her it was indiscreet.

Lately, Philip has grown a beard, he tells her. Send me a photo so I can see what you look like now, Elizabeth wrote, and when it arrived, she studied it carefully. She doesn’t find him as handsome with a beard, but at least it would keep Crawfie quiet.

She put it on the mantelpiece in place of the photo her old governess thought so revealing.

‘There, no one will recognise him now,’ she said, but Crawfie only gave her one of her looks.

He is still in South East Asia but it cannot be long before the war is over there, too, and then surely, surely, he will be able to come home?

And what then? No promises have been made. Photo or no photo, Philip may have changed his mind. In all the joy of the war ending, Elizabeth is ashamed that she still has a wish left: that Philip will still want her.

‘Lil, are you ready?’ Margaret bounces in only to recoil at the sight of Elizabeth in her uniform. ‘Why are you wearing that? It’s awful!’

‘It’s my uniform,’ Elizabeth says quietly. ‘I want to.’

Margaret rolls her eyes at her sister’s choice of outfit. ‘They want us out on the balcony,’ she says. ‘Papa says we can’t keep people waiting any longer.’

‘I’m coming.’

Susan trots importantly along beside Elizabeth as she walks along the interminable palace corridors towards the room overlooking the forecourt where they always gather before appearances on the balcony.

This is the official day of celebration, although the jubilation has been going on since Churchill’s announcement the day before. All night, fireworks streaked across the sky and the crowds surged through the streets.

The sense of relief is profound after six long years of war. They all feel it, a slackening of tension, a great unloosening, a collective exhalation, as if the country has been hunched in on itself, holding its breath and is now letting it go in an outpouring of emotion.

When she first heard the news, Elizabeth’s heart had pounded so hard that she had had to press a hand to her chest to stop it breaking through her ribs. At last, at last! For a brief moment the relief had been so intense that it was painful.

Now poor, battered London has erupted in celebration. People who have lost everything but their lives are converging on the palace, clambering over the Victoria Monument and pressing up against the gates.

The room that overlooks the forecourt is full of people. Everybody is smiling and chatting and the noise both inside and out is deafening. Elizabeth is delighted to see her father’s thin face relaxed for once. It lights up when he sees her.

‘There you are,’ he says as the chants of ‘We want the King!’ grow ever more insistent. ‘Ready?’

Elizabeth nods, and waits for him to extricate the Queen from a conversation with her favourite brother, David Bowes-Lyon, and send his equerry, Group Captain Townsend, to gather up Margaret.

‘It’s worse than trying to herd the corgis,’ the King pretends to grumble.

At last the four of them are all together. The King glances at the Queen, who smiles back at him in a wordless conversation. There is a bond between them that Elizabeth envies. She would like to be married to man who would look at her the way her father looks at her mother.

Philip is not like her father.

‘Out we go,’ the King says. ‘Just be careful, though. The balcony is a bit shaky after that bomb.’