‘I don’t mind as long as I can wear it,’ she says. ‘I must wear it!’

The jeweller bows. ‘Then wear it you shall, Your Royal Highness. I will be as quick as I can.’

‘Now,’ says the Queen when he too has gone, ‘let’s all calm down.’

Elizabeth’s earlier feeling of serenity has completely deserted her, but she knows her mother is right. She thinks about Philip and how he would react to a broken tiara, and instantly feels steadier. He is what is important today, she reminds herself, pressing her fingertips to her chest to slow her breathing.

It enables her to stand still while they deal with earrings, and shoes, and the long, beautifully embroidered veil is carefully pinned to her hair awaiting the crowning touch of the repaired tiara, but as time ticks on and there is no sign of either Jock or the jeweller, Elizabeth begins to fret again. She wants to pace but she can’t with the veil on. She twists her hands together instead. What is she going to do with her hands during the walk up the aisle?

‘My bouquet!’ she exclaims, suddenly realising she hasn’t seen it yet. ‘Where is it?’

There are glances of consternation around the room. Nobody knows. ‘It’s been delivered,’ the Queen says, ‘I’m sure of it.’ Although she doesn’t sound sure. ‘It must be somewhere.’

Summoning a footman from the corridor outside, the Queen sends him to organise a search for the missing bouquet, and Norman Hartnell delegates two of his team to help them. Elizabeth can hear the sound of footsteps running along the corridors and doors being unceremoniously flung open.

There is still no sign of the bouquet when the jeweller comes back. Everyone lets out a simultaneous sigh of relief as he slides the tiara safely onto her hair, followed by another as a panting, red-faced dresser returns with news that the bouquet has been found in the porter’s lodge icebox.

‘A footman put it there to keep it cool so it could be given to you at the last minute,’ the dresser says. ‘But then he went off duty and forgot.’

‘Now we just need Jock with the necklace.’ Elizabeth’s hand keeps straying to her throat where the pearls will nestle.

‘It’s almost time,’ the Queen says anxiously. She is wearing a flattering dress in an apricot-coloured silk brocade. ‘I need to go, I’m afraid. They’ll be waiting for me downstairs. I’m going in the car with Margaret.’

‘All right, Mummy.’ Elizabeth kisses her mother. ‘See you at the abbey!’

‘Best of luck, darling.’

The bridesmaids have been getting ready in another room and they can be heard chattering and laughing as they go past the door on their way down to the entrance where a fleet of Daimlers are lined up to take them to the abbey along with the rest of the royal party. Elizabeth and her father will leave last.

Outside, the crowd are stirring in anticipation too. Singing and sporadic cheering drift up from the Mall.

‘You should start heading down too,’ Bobo says in a practical voice after the Queen has gone. ‘You can’t move very fast with that train.’

‘The necklace—’

‘I daresay Mr Colville will be able to find you when he makes it back from St James’s Palace.’

‘All right.’ Elizabeth starts to nod and then thinks better of it with the tiara and veil. ‘I think we’re ready, aren’t we?’

‘As ready as we’re going to be.’ She beckons to one of the Hartnell dressers to help with the train. ‘Here, we’ll take the veil, you just concentrate on walking in the dress.’

They have almost reached the top of the stairs when Jock Colville comes running up them. Elizabeth stops.

‘Did you get it?’ she asks eagerly, and Jock’s smile is triumphant as he pulls the pearl necklace from his pocket.

‘Sorry I took so long, ma’am,’ he says. ‘I commandeered the King of Norway’s Daimler before I’d given the king a chance to get out, but in the event, we couldn’t get through the crowds in the car, so I got out and ran, fighting my way through everybody.’

He hands the pearls to Bobo, who undoes the clasp and puts them around Elizabeth’s neck.

‘When I got to St James’s, it was deserted. Everyone is already at the abbey and there was only one aged retainer who had no intention of letting me in. Of course, I left in such a hurry, I didn’t have any way of proving who I was! There is a police guard and they tried ringing here, but the switchboard operators have been given the day off.’

‘What did you do?’ asks Elizabeth, thrilled to be able to pat the pearls into place at her throat.

‘Eventually I had the brainwave of showing them the wedding programme with my name on it, but even so two policemen insisted on coming back to the palace with me. I don’t think they quite trusted me!’

‘Well, I’m very grateful, Jock. Thank you.’

‘My pleasure, ma’am.’

The pearls have steadied her. She is ready now, nervous still but it is a simmering low in her belly, not the frazzled, fluttery feeling in her chest she had before.

As Elizabeth makes her way slowly down the stairs, she can see the Life Guards on horses trotting out through the arch. For the first time since the war, they are in their ceremonial uniforms rather than battle dress and they look splendid in their plumed helmets, scarlet tunics, and steel cuirasses. It lifts her heart to see them and judging by the roar of approval from the crowd on the other side of the gates, they have the same effect on everybody. The Queen and Margaret follow in a sedately driven Daimler, followed in their turn by an escort of the Horse Guards in all their ceremonial glory.

The horses look wonderful, Elizabeth thinks. They are all groomed to a gleam, their manes and tails carefully dressed, and their harness glittering.

Her father is waiting for her, looking emotional but managing a smile as she reaches the bottom of the stairs. ‘Lilibet … you look beautiful.’

‘Thank you, Papa.’

‘I just pray that you and Philip will be as happy as Mummy and I have been.’

‘I hope so too,’ she says.

Pulled by four superb Windsor Greys from the Royal Mews, the Irish State Coach has moved forward under the portico. The horses stand patiently, shaking their manes occasionally. Elizabeth catches the eye of Cyril in his full scarlet and gold livery. He has been her footman for ten years and she invited him to the wedding in the abbey, only for the idea to be vetoed by the sergeant footman.

‘He says I’m on duty,’ Cyril told her. ‘I’ve got to go on the carriage, he says. At least I’ll get a good view!’

Elizabeth likes knowing he will be close, and when he lowers an eyelid in a wink, her face relaxes into a smile.

A roar on the other side of the arch indicates that the Queen and Princess Margaret have come into view.

‘Our turn,’ the King says, sounding strained.

Very carefully, Elizabeth is helped into the coach, the dressers piling the billowing train in after her. The King gets in beside her and there is a little jolt as the coachman gives the horses the word to walk on, a further escort of the Horse Guards falling in behind them.

‘We’re off,’ says the King. ‘It’s not too late to change your mind,’ he jokes.