I wake, tucked up on the library couch, in the velvety dark of deep night.

But tossing and turning. Freezing yet too tired to get up, get another eiderdown, yet the cold is nagging me, just won’t let me sleep. Eventually I leap up, furious, and throw on an extra jumper. Flit by the window.

A thick smoke has dropped over Campden Hill Square, wrapping it up in silence and stillness. It must be a fog. I’ve read about them. It’s so beautiful but lordy, why does everything feel so much worse at night? All the worry that’s crowding into my brain, clanging me awake . . .

The horror of an empty Christmas ahead, of our bleak future trapped in this house, the horror of little Pin’s face when he asked, ‘Kicky, what’s happened to Father Christmas? He’s not going to find us this year, is he. Doesn’t he like us any more?’

Suddenly, gloriously, it hits me.

If no one else is going to give us a Christmas and welcome Santa into this place, then I have to make it happen myself. Of course! Charlie Boo’s right: I’m as close to a parent as our family’s now got. They’ve gone, I have to accept it. I can’t replace our parents. I can’t make someone else either, I can’t force anyone into that. I can’t be them. But I can be something else, a new thing for my family, someone who makes things happen in ways we don’t expect. So. Stop relying on others, stop getting cross at everything, just do it. Sparkle up my siblings’ lives and stop waiting for someone, anyone, to make our future right. I can do it. I’m from the bush, I’ve had enough practice. I’ve spent a lifetime getting by.

Family presents? Obvious. Hundreds of glorious things just waiting in the attic. Wrapping paper? Old newspaper. Up there too. Decorations? Paper chains. Cut-out snowflakes. Ribbons from the shop dummies’ clothes. Easy. It’ll all be done on Christmas Eve, I’ll spend the entire night transforming the Reptilarium and they’ll wake up in the morning in shock. It’ll be for Scruff and Berti, yes of course, but for dear little Pin most of all.

I fling up the window pane and breathe deep. Life: sorted. ‘If you want something done the way you want – then just do it yourself. Don’t wait for the light at the end of the tunnel – stride down there and light the blasted thing yourself.’ Dad’s always telling us that and he’s so right.

A wail, like a cat. Next door.

I lean out. Dinda never mentioned she had a pet.

Good grief! Up a tree, at the front of her house, the branches are shaking. There’s someone there. She’s being robbed!

I lean further out. There’s . . . something . . . through the fog . . . balancing on a branch like a tightrope walker with some kind of rope around their neck. They’ve got a big hump on their back and are making their way, inch by inch, towards a slightly opened bow window on the second floor. The drop below them is enormous – two storeys. The window they’re aiming for has a single candle in front of a big pile of gifts, which are wrapped in newspaper with thick black ribbon and bows. The robber wobbles, rights themselves, and creeps closer and closer to the candle. To the very stylish gifts.

The gifts.

Oh no. I almost fall out my own window to get a better look.

Berti?

Bert!

Noooooo! The drop’s too far, the branch too narrow, she can’t do this. She’s not the climber of the family, she’s the one who stays inside in all her paleness and gothic splendour and makes hats. It’s as if she senses eyes suddenly on her – she wobbles, loses her footing. My heart lurches; on the ground below her are these horribly cruel-looking and hard paving stones that will do terrible things to her little bones, her skull – what to do?

The drop’s too big. She’ll die. My sister will die. My infuriating sister who I’m always saying I want to wring her neck but no, not at all. Desperately I want to yell ‘Berti, back, girl, back!’ but it’ll break her concentration, she’s so unsteady up there but so focused on getting to that window; I’m not sure she’ll make it because the branch doesn’t look like it’ll hold her weight and she’ll never haul open the heavy pane by herself and I’m locked inside the Reptilarium, stuck.

Hang on, how did she get out?

I race through the library, banging on doors and scrambling down ladders. ‘Scruff! Basti! Pin! Wake up. It’s an emergency. Bert’s in the tree next door, she’s going to fall, can’t last much longer. We need to get to her.’

Scruff and Pin come running. ‘Basti! Basti!’ We all yell. No answer – he must be asleep – can’t hear. We’ve no idea where his bedroom is, which door out of the hundreds in this house.

We stop abruptly by Perdita’s cage. Empty, its door wide open.

I groan, ‘Nooooooooooooooo.’

Of course . . . the rope around Bert’s neck isn’t a rope at all. It’s a very alive – and very deadly – snake. Her latest fashion item, the scarf she’s always wanted, and the new pet she’s been continually eyeing off. Her new Bucket. Who won’t appreciate being out of its cage, on a wobbly branch, in the freezing cold. Can it get any worse?

No. No it cannot. I love that fierce, funny girl.

Front door: firmly shut. Scullery window: locked. Uncle: vanished.

No way out.

A cold gust of wind suddenly blows through the house. Where’s it coming from? There must be another room, an open window . . . but where?

‘Arrrrgh,’ I groan in frustration.

‘Kick, over here!’ Scruff shouts.

A wooden panel, to the right of us. Opened. A secret entrance in the wall. A disguised door that’s been slid across. How on earth she found it . . . one of her nocturnal wanderings looking for ghosts, no doubt.

We race through it. To a tiny study with a narrow window like a castle’s. Which is ajar. Just wide enough for Bert’s slenderness to squeeze through. We get Pin out but then I try. Scruff. Nup. No good. Head first, shoulders first, feet – but we can’t, we’re too big, I’m almost tearing off my skin trying to do it but it just won’t work, too many bones in the way.

A bloodcurdling scream. As if Bert’s just realised the impossibility of the task she’s set herself, as if she’s completely stuck. We’re coming! Pin starts crying on the other side of the window. Scruff and I race back to the entrance hall.

‘Ba-sti!’ I yell with all my might. ‘Bert’s gone – she’s stuck next door – is going to fall – she’s going to die!’

‘BAAASTIIIII!’ Scruff and I now scream, banging on any door we can find. Where is he?

He emerges.

Bewildered, lost, from a vastly deep sleep. ‘Wh-what’s going on?’

‘Bert – Perdi – next door – up the big tree – we’ve got to get them. Save them. The branch can’t hold her.’

Basti’s face drains of colour.

From outside, another bloodcurdling scream, as if Bert’s moments away from plunging to her death.

‘Quick!’

Basti races to the front door fumbling with his keys. So many – which one – he takes them from his neck – hands shaking – finds it but is trembling so much he can’t get the key into the lock! He drops them. We groan. Pin starts crying on the other side of the door.

‘Come on, come on.’ Basti has to start all over again.

‘We’re running out of time,’ Scruff yells in despair. It only makes Basti more fumbly.

‘Give them to me.’ I grab the keys firmly and go through them, methodically, one by one, just as Dad would – supernaturally calm the scarier a situation gets (whether King Brown on car seat or empty fuel tank in middle of desert: always making things right).

Turn the lock.

‘Thank you!’ Basti claps me on the shoulder.

But Bert’s screaming continuously now, as if she’s clinging on by her black-painted fingernails. We rush outside. No time to lose.

Through the thick fog we can just see her now hanging off the window ledge, her pale legs kicking in the empty air, her thin arms clinging on for dear might. Perdita’s wrapped in terror around her neck. She’s wailing, ‘Daddy,’ over and over again.

‘I’m here, Bert,’ I yell, ‘I’m coming. Hold on, little sis!’

‘Kicky, oh Kicky, help me.’

I race to Dinda’s door and thump furiously – no answer – no one home. Try desperately to climb the tree but can’t, it’s too slippery, damp, smooth; can’t get a foothold. Scruff tries too but doesn’t get any further, then Pin, darling Pin and he only manages three feet. Scruff and I are both champion bush-climbers, leaping up the water tower in seconds and shimmying up ghost gums, but this is impossible in the fog, the bark’s too smooth and slippery, we can’t get a grip.

‘The fire brigade won’t arrive in time,’ Scruff cries. ‘She can’t hold on much longer. She’s going to die, Kick!’

One of Bert’s hands slips off the windowsill and she dangles sickeningly. Everyone screams. Directly below her is a row of horribly sharp spikes on the wrought iron fence in front of Dinda’s house. What to do, what to do?

‘I’m coming, Miss Albertina.’

It’s Basti.

Scruff, Pin and I turn. Stare. At our uncle. Rolling up his pyjama legs, adjusting his night cap and slipping off his shoes. Spitting in his hands and rubbing them together. The Basti who never goes out. Who can’t get a grip on the modern world. Who fails to fit a key in a lock. I gaze up at the enormously tall tree – oh lordy, can’t have two members of my immediate family crashing to the ground and killing themselves here.

‘Basti, you can’t –’ I want to add that he’s far too old for this but don’t dare.

Because there’s a look of such determination on his face.

‘Just watch me, troops.’

He starts to climb the impossibly smooth trunk. In the dark. The damp. Like he’s done this his entire life. Like he knows exactly where to place each foot, curling his toes in an expert monkey grip – higher and higher – firm and fast.

The rest of us step back in awe. This, our key-fumbly, sleep-addled uncle. There’s only one word for it: miraculous.

‘I’m coming, Miss Albertina, just hold on.’

Bert manages to get both sets of fingers back on the window sill but her grip’s slipping, she’s getting weaker, moaning, she won’t be able to hold on much longer. Come on, girl, I close my eyes and pray, come on, just a bit longer, you can do it.

‘Basti,’ I urge, trying not to panic Bert, ‘quick.’

Perdita’s still wrapped around Bert’s neck, clinging tight – it isn’t helping. As fast as Basti’s climbing, he won’t be fast enough. Bert gurgles – it looks like the snake’s now accidentally strangling her in its fright. Basti keeps on climbing, swiftly, surely, as if he’s done this a thousand times before.

Which, perhaps, he has.

A new uncle entirely.

But is it enough?

Dinda suddenly appears, walking up the hill with a concert programme under her arm. She takes in the commotion and screams as she sees Bert, who’s clinging on for dear life and mewling like a terrified kitten now with her legs flapping in the air.

The scream makes Bert lose her grip again. We all exclaim in horror. She swings her hand up and catches the sill but it’s obvious – horribly obvious to all of us – that she won’t last much longer.

Basti keeps climbing steadily. Faster, faster, unfazed by the noise below him. He balances across the long, bending branch as nimbly as a circus performer. Will it hold both their weights? It’s not strong enough. It creaks, Bert’s grip is slipping, the branch creaks again, Bert’s hands are now sliding from the white sill.

‘Baaaasti,’ I cry. The branch is not going to last, is bending most terribly, is almost gone . . .

Bert loses her grip.

Aaaaaaaargh!

Basti lunges down . . . catches his niece strong . . . the branch snaps.

Both of them come crashing, smashing down, down through the branches, to the horribly hard ground way below them. Bert is cradled tight in her uncle’s arms, just missing the horrible spikes.

Thud.

She lands on top of Basti.

Everything is most horribly, silently . . . still.

We all stare, breaths held, at Bert splayed on Basti, a jumble of limbs.

Everything askew. Quiet. Too quiet.