That evening, as Alicky was leaving Marie and Anastasia’s bedroom after listening to them say their prayers and after kissing them goodnight, one of Alexei’s nurserymaids came hurrying down the corridor towards her, an anxious expression on her face.

Dipping a curtsey, she said, ‘There is no cause for alarm, Your Imperial Majesty, but there is a little spotting of blood on His Imperial Highness’s swaddling bands and—’

She got no further.

Alicky’s hand had flown to her throat. To the nearest of the footmen who lined every yard of every corridor, she said, ‘Inform his Imperial Majesty his presence is needed in the nursery.’

And then, struggling not to let her alarm show, she headed swiftly and with fast-rising fear to her precious son.

In the lamplight Alexei was lying in his cradle, freshly bathed, sweetly-smelling and nightgowned, cooing happily. There was no sign of him being even remotely distressed.

‘The blood,’ she said tightly to the head nursery-nurse. ‘Where did it come from?’

‘His navel, Your Imperial Majesty. And it was only a few spots. Hardly anything at all.’

With a thudding heart Alicky leaned over the cradle. As she lifted up Alexei’s linen nightgown, the head nursery-nurse said, ‘I swabbed the spots away. There will be nothing to see, but if you would like to see the swab?’

Alicky wasn’t listening to her. She was undoing the safety pins holding Alexei’s muslin nappy together. As the nappy fell away, there were fresh drops of blood on its inner folds. More drops were oozing from his tummy button.

The head nursery-nurse said, perplexed, ‘But it had stopped, Your Imperial Majesty! I can show you the swab I used. I—’

She fell abruptly silent as Nicky strode into the room. Taking one look at the beads of blood, he said, white-lipped, ‘Summon the doctor.’

As the nurse hurried from the room, Nicky said to the nurserymaid, ‘Leave us.’

The girl did so, unable to imagine what all the fuss was about. Her mother had had twelve babies and would not have blinked an eye at a few spots of blood leaking from the navel. It was certainly nothing for the Tsar and Tsarina to worry about; and the doctor, when he came, would tell them so.

In the room behind her, Alicky and Nicky looked at each other with horror-filled eyes.

‘Is it possible it is natural bleeding?’ A pulse throbbed at the corner of Nicky’s jaw.

Although he knew that one of Queen Victoria’s sons had died from haemophilia and that Alicky’s brother and Irène’s little boy had, too, and that others in Alicky’s family suffered from it, he had always been confident that his Romanov bloodline would ensure that the sickness wouldn’t affect any son he and Alicky had. Now, however, he was filled with terrible doubt.