‘Why you cry, Cholliemurrum?’ asks Harby softly. ‘Where DaRA?’

‘He’s in hospital, having an operation. Because something’s wrong with his heart,’ I blurt out. My raw voice sounds more angry than I mean it to.

Harby draws back, not understanding, his eyes confused and frightened. He tries again. ‘You not make safe DaRA?’ he whispers.

He doesn’t mean it like an accusation, but that’s how it feels. I turn on him, shooting arrows with my eyes. ‘No, Harby, I wasn’t good and kind like you; I didn’t even try to make my brother safe; I just took one look at him and ran the other way. And now … it’s too late, because here I am … HERE …’ I wave my arms in the air, I’m yelling now and Harby’s staring, wide-eyed and open-mouthed. ‘… I’m stuck HERE in the STUPID STONE AGE with YOU and I don’t know how to get HOME!’

Home … home … home. My word echoes back to me from across the valley like a taunt. A cloud of ragged crows rise like witches’ handkerchiefs from a tall tree.

‘Home,’ murmurs Harby. His voice sounds little and lost.

My silly anger melts and a new lump forms in my throat. ‘Do you remember your home, Harby?’ I ask him softly.

Harby shakes his head and fiddles with his spear.

I bite my lip. Even though Harby’s in his own world, he’s just as stuck as I am. ‘Sorry,’ I whisper.

He shrugs. Maybe they don’t have a word for sorry in the Stone Age. Maybe when they make mistakes they … do something else to make it better.

‘I’ll help you, Harby.’ I joggle his arm gently. ‘When we get off this stupid ledge, we’ll do it together – we’ll find Mothga, we’ll find your home, we’ll make safe.’

Harby stares at me with those eyes that are black and forever-deep, like the unexplored parts of the sea.

‘I help you, Cholliemurrum,’ he whispers hoarsely, joggling my arm back with his pinchy fingers. ‘We find DaRA. We find your home. We make safe.’

‘OK,’ I say, smiling through my teary eyes. And I hold my hand up for a high five.

But Harby just looks at my hand for a second and then holds his own hand up. ‘OK,’ he says solemnly.

And it feels like we’ve made a promise.

‘OOOOOWEEEEEEE!’ hoots an early owl close by.

‘Ooooooowooooooooo!’ comes another owl’s answer.

Evening is coming and the light is soft. Harby bends his blue-bandaged head over his spear once more. I lie down on my side and gaze out across the wild glowing valley. We wait. Behind me I can hear the rhythmic scrape-scrape sound of Harby beginning to sharpen his spear again.

I squeeze my eyes tight shut and picture Dara in his little fish-tank bed. I wish I’d held him back there in the hospital. I wish I’d given him a big cuddle and told him that everything would be all right. ‘Sorry, Dara,’ I whisper, and I open my eyes and gaze over at where, in my Mandel Forest, the hospital would be. He could be having his operation right now. ‘Make safe, Dara,’ I say in my warrior voice, like I’m making him a promise too.