I sighed and put my pencil down. ‘But if you don’t know who he is, why did Pa wave at him?’

Mutti said nothing. She was sketching a cloud, shading and shading its full, grey shape until it looked as if it were about to burst with rain.

‘And wasn’t he the man who was so horrible to you in the bakery? You said he had lost his brother in the Great War. You knew him.’

‘Please, Pet,’ Mutti said. ‘Can we talk about this another time? I have so much on my mind today.’ Her fingers tightened on the pencil and the cloud grew darker.

Barnaby the cat prowled into the lantern room then – the lion of our lighthouse. He trotted towards me, leapt on to my lap and patted my pencil with a huge fluffy paw. Then he sniffed at my sketchbook, and lay down on it, his big soft belly eclipsing my scribble. I sighed and gave up.

Mutti looked at me, then turned back to her raincloud. ‘Everything has a song, Pet,’ she said. ‘If you listen carefully to the song of something as you are drawing, it will help you to capture its soul.’

I listened, trying to let go of all my questions for Mutti’s sake, trying to hear the song of the sea. The sea has many different songs, I thought. There are days when its song could be played upon a harp, but on this day it would have been something much more solemn: a slowly-bowed cello, perhaps. The water was like mercury – heavy and quivering.

I was starting to understand what Mutti meant, but I still couldn’t draw it.

Then there was a high, whistling noise from the speaking tube, and Mutti leapt up. Barnaby leapt up too, digging his claws into my legs as he flew from my lap and disappeared down the stairs. My sketchbook and pencil clattered to the floor.

The speaking tube is a long hose that goes between the lantern room and the kitchen below. Mutti removed the whistle from the brass end of the tube, and put it to her mouth. ‘I’m here,’ she said. ‘Is there any news? Has it arrived?’

It must have been Pa, down in the kitchen. We usually used the speaking tube to tell Pa that dinner was ready, or he might use it to ask us to bring him up a cup of tea. This conversation sounded a lot more serious.

‘When?’ Mutti asked, and pressed the brass piece to her ear once more. The long, white hose wriggled and shook in her hand.

‘But that’s so soon,’ she said, and she sank back into her chair. ‘That’s the day after tomorrow.’

‘What is, Mutti? What’s the day after tomorrow?’

But she was listening to Pa. Eventually, she fixed the whistle back into the brass mouthpiece with shaking hands.