“I’m sorry. I can’t stay.”

What does it matter? It’s only a photograph. But that photograph! But is it worth losing a new-found sister over? These thoughts race through my mind as I sit on the last train home, watching my reflection in the window as it fleets over the darkening fields and woods. The face in the window, colours washed out in the dusky light, has the same shape and contours as the face in the sepia photograph. When she smiles, the smile is the same.

Next day I telephone Vera.

“So sorry I had to rush off. I’d forgotten I had an early morning appointment.”

A few days after the botched tribunal, Eric Pike calls round at my father’s house in a big blue Volvo estate. He and my father sit in the back room amicably discussing aviation, while Valentina and Stanislav run up and down the stairs piling all their possessions in black bin bags into the back of the car. Mike and I arrive just as they are ready to leave. Eric Pike shakes my father’s hand and takes the driver’s seat, and Stanislav and Valentina squeeze into the passenger seat together. My father hovers on the doorstep. Valentina winds down the window, sticks her head out and shouts, “You think you very clever, Mr Engineer, but you wait. Remember I always get what I want.”

She spits, “Phphoo!” The car is already moving forward. The gob of spit lands on the car door, hangs for a moment, and slides slimily to the ground. Then they are gone.

“So are you all right, Pappa? Is everything all right?” I give him a hug. Under the cardigan, his shoulders are bony.

“All right. Yes everything all right. Good job. Maybe one day I will telephone to Valentina and seek reconciliation.”

And now for the first time I hear a new tone in my father’s voice: I realise how lonely he is.

I telephone Vera. We must make plans for how Father is to be supported now that he is on his own. Big Sis is all for getting him certified and carted off to a residential home.

“We must face the truth, Nadezhda, unpalatable though it is. Our father is mad. It’s only a matter of time before he gets into some other lunatic scheme. Better put him where he can cause no more trouble.”

“I don’t think he’s mad, Vera; he’s just eccentric. Too eccentric to live in a home.”

Somehow, I can’t see my father with his apples and his tractor talk and his strange habits fitting easily into the routine of a residential home. I suggest that sheltered housing, where he will have a greater degree of independence, might be more suitable, and Vera agrees, adding with strong emphasis that this is what should have happened in the first place. She thinks she has scored a victory. I let it pass.

After Valentina and Stanislav had left, I cleared out enough rubbish from their rooms to fill fourteen black plastic bin bags. Out went the soiled cotton wool, the crumpled packaging, the cosmetics bottles and jars, the holey tights, the papers and magazines, mail-order catalogues, junk mail, discarded shoes and clothes. Out went the half-eaten ham sandwich and several apple cores and a decayed pork pie which I found under the bed in the same place I had once found a used condom. In Stanislav’s room I discovered a little surprise-a carrier bag full of porn magazines under the bed. Tut tut.

Then I turned my attention to the bathroom, and with the help of a wire coat-hanger pulled out a sticky clump of matted blonde hair and brown pubic hair that was clogging the bath outlet. How was it possible for one person to generate so much mess? As I cleaned I realised with a flash of insight that Valentina must have had someone to clean up after her for most of her life.

I set to work in the kitchen and pantry, clearing off the grease from the cooker and surrounding walls-it was so thick I scraped it off with a knife-throwing out scraps of food, mopping up sticky patches on floors, shelves and worktops where unidentified fluids had been spilled and never wiped up. Pots, jars, tins, packets, had been opened, started, and then the contents left to fester. Ajar of jam left open in the pantry had cracked, turned rock hard, and stuck to the shelf so fast that as I tried to pull it away it shattered in my hands. The shards of glass fell to the floor among a debris of newspaper, empty boil-in bags, spilled sugar, broken pasta shells, biscuit crumbs and dried peas.

Under the sink, I found a stash of tinned mackerel-I counted forty-six tins altogether.

“What’s this?” I asked my father. He shrugged. “Buy one get one free. She likes.” What can you do with forty-six tins of mackerel? I couldn’t throw them away. What would Mother have done? I took them and distributed them to everyone we knew in the village, and gave the rest to the vicar, for the poor. For several years afterwards, tins of mackerel turned up in little heaps before the altar at harvest festival.

In the outhouse, in a cardboard box, were several packets of biscuits. All had been opened, and crumbs and bits of wrapping were everywhere. In another corner were four mouldy loaves of white sliced bread. Again, all the packets were torn open and their contents scattered. Why would someone do that? Then I noticed something large and brown scurrying in the corner.

Ohmygod! Call the council, quick!

In the sitting-room, kitchen, and pantry, saucers of food and milk had been put down for Lady Di which had not been to his taste, and they too had been left to rot in the August heat. One was infested with brown mushroom-like growths. In another, white maggots were squirming. The milk had soured to a green cheesy slime. I put the saucers to soak in bleach.

I am not usually the sort of woman who finds cleaning therapeutic, but this had the feel of a symbolic purging, the utter eradication of an alien invader who had tried to colonise our family. It felt good.

I am cautious about mentioning to Vera that my father has talked about reconciliation with Valentina, for I know that if there is one thing that will surely drive him back into her arms, it is a confrontation with Big Sis. But somehow I let it out.

“Oh the fool!” I can hear her intake of breath as she chooses her words. “Of course you social workers are familiar with this syndrome of abused women clinging to their abusers.”

“I’m not a social worker, Vera.”

“No, of course, you’re a sociologist. I forgot. But if you were a social worker that is what you would say.”

“Maybe.”

“So I think it’s so important to get him out of harm’s way, for his own sake. Otherwise he will simply fall victim to the next unscrupulous person to come along. Weren’t you supposed to be looking for some sheltered housing, Nadia? Really, I think it’s time you started taking some responsibility, as I did for Mother.”

But my father is determined to make the most of his new freedom. When I raise the possibility of sheltered housing, he says he will stay where he is. He is far too busy to consider moving. He will get the house in order, and maybe even rent out Valentina’s old room on the top floor to a suitable middle-aged lady. And then he still has his book to write.

“Did I ever finish telling you about the half-tractor?”

He reaches for the narrow-lined A4 notepad, which is now almost full with his masterwork, and reads:

The half-tractor was invented by French engineer by the name of Adolph Kegresse, who had worked in Russia as technical director to the Tsar’s automobile fleet, but at the time of the 1917 revolution he made his way back to France, where he continued to perfect his designs. The half-tractor is based on the simple principle of normal tyred wheels in front of vehicle, and caterpillar tracks at back. The half-tracked tractors, cavalry cars and armoured cars were especially popular with the Polish military, where they were deemed suitable for driving on the country’s poorly maintained roads. The historic union of Adolph Kegresse with Andre Citroen is said to have given birth to the whole phenomenon of all-terrain vehicles. In their time these seemed to promise a revolution in agriculture and heavy transport, but alas they have become one of the curses of our modern age.