Judged by any standard, my sister Julie would not have been numbered among all things bright and beautiful. Neither bright nor beautiful, perhaps, but rendered strangely powerful by the air of helplessness, of defencelessness, which she exuded.

At thirty-five, her figure had rounded, a roundness accentuated by the fact that she invariably wore white or pink or a combination of the two. One of the women whose husbands she had wheedled away and then married, had, I heard, described her as a marshmallow.

‘Why a marshmallow?’ a friend had enquired, puzzled.

‘Soft, overly sweet and with very little substance,’ had been the somewhat bitter, but startlingly accurate, reply.

Julie’s appearance had changed very little over the years: the large, slightly protuberant, unusually pale blue eyes continued to blink pathos, the unremarkable nose to wrinkle when she was not pleased, the rather slack mouth to settle as easily into a pout when she was crossed, the fair curls, which fell on to her forehead, to curtain a calculating assessment of what she could get people to do for her..

It was not difficult to imagine her in a playpen.

I was eight years old when my parents had their second child, another daughter. They were delighted; I reserved judgement.

My mother had gone back to work when I was two and I had been left first at a crèche, then at a pre-school and then at the after-care of Pinewood Primary School, until she fetched me at five each day.

Perhaps as a result, I had become an independent, self-reliant child. From an early age, I insisted on doing things for myself even if I had to struggle – and taking responsibility for my actions. A characteristic I have carried with me into adulthood.

‘Far too independent,’ my husband often said. ‘Why won’t you let me help you?’

‘Thanks, I’ll manage’ – my usual reply – became a catch phrase in our home. Even today, my children tease me with it. When I telephone and ask Jonathan, on loan to an electronics company in Singapore, whether he has found suitable accommodation, he says, ‘Thanks, I’ll manage.’ When I ask Janet, at present teaching on supply in London, how she will find her way to so many different schools, she replies, ‘Thanks, I’ll manage.’ And, although they are laughing at me, I catch an echo of my own voice in theirs.

Everything changed in my childhood home when Julie was born.

My father had had a significant promotion and so there was no need for my mother to return to work. She was therefore able to devote all her time and attention to the new arrival, who very soon learned to get her own way by either sulking or screaming if her every need – or even desire – were not immediately satisfied.

‘Remember, she’s only a baby,’ I was told when she threw her dummy out of the cot time and time again and I had to pick it up, rinse it and return it to her.

‘Remember, she’s still a baby,’ I was told when, as a toddler, she broke my Barbie doll and scribbled in my books.

‘She’s only a little girl, really,’ I was reminded when, as a five-year-old, she refused to do up her own buttons and I had to interrupt whatever I was doing in order to dress her.

And when she went to school, she interpreted my mother’s request that I help her with her homework as meaning that I was to do it for her.

There is no doubt that she succeeded in manipulating my mother and me to an extent. But it was our father who doted on her – was almost obsessed with her — and she had only to cuddle up and flap her eyelashes at him to have him agreeing to anything she wanted.

Although I looked very much like him, having inherited his dark hair, his rather pointed features, his energy, I was forced reluctantly to accept that I did not give him as much pleasure as my sister did and never had. He probably sensed my disdain of courting other people’s good opinion of me, especially his. If I could not please him as I was . . .

While I took delight in achieving, in setting myself goals, in competing with myself, Julie staggered through school, toppling precariously into the next standard at the end of each year until eventually she had to repeat one.

But she made up in charm and persuasiveness for what she lacked in intellectual capacity. Even when she was in the grades, she had small boys arguing about which of them would have the honour of carrying her small suitcase home for her.

‘My mother really should have bought a lighter one. This one is far too heavy for me,’ she would say with a sigh, and they would come running.

It had not taken her long to discover that victims attract rescuers.

So, when she was eight, her arm suddenly became too sore for her to carry her own chair back to the hall. Or, when she was older, she said she had a blinding headache and had not been able to see the board, would someone please copy out the notes for her? And, when she was a teenager, she let it be known that her bicycle had a puncture and that she really didn’t know how to fix it, nor was she strong enough to pump the tyre. Could someone . . .?

And the ‘someone’ was always male. A male who felt flattered by her need of him.

By the time she left school at nineteen with a very shaky certificate, I was married to Ed and our son and daughter had been born.

Her first job was as an assistant in a delicatessen, one which stayed open until eight in the evenings to provide take-away suppers. The owner’s wife did the early morning shift and Julie took over from her at noon and stayed on until closing time. She told me that she often needed to ask for – and got — assistance in carrying trays from the kitchen and in ringing up the right amount at the till. Looking helpless obviously paid off.

She didn’t like the work – but she did like the owner. The doors closed at eight but, after a time, neither of them left the building until much later than that.

Within a year, the couple were divorced and Julie had become Mrs Delicatessen. But the owner now employed other people to work the morning and afternoon shifts and his new wife stayed at home.

That marriage lasted just over two years. Lasted until she met an old school friend in a coffee shop one morning.

After they had caught up on each other’s news, the friend asked casually, ‘And where do you and Miguel go for your holidays?’

‘Oh, we don’t ever have holidays — he can never leave the business.’

‘Do you think he would mind if you came away with us for a week? We’ve booked a seaside cottage, only Pete will be fishing all day and I’d love to have your company.’

But on that holiday, it was Julie who did the fishing. Attracted to Pete from the start, she lost no opportunity of feigning ignorance or incompetence to enlist his sympathy, of asking him to fasten the clasp of her chain because her hair kept getting in the way when she tried, to dry her back after she had been swimming. The friend certainly noticed, but she said nothing. Said nothing – and wondered, so she told me when, much later, I met her.

Pete was a sales representative for a hardware company and he took to calling in to visit Julie during the day while her husband was at work. Julie, who always had something that needed fixing, a light bulb that need changing, a tap that was leaking. And, of course, she was so visibly grateful for his help, didn’t know what she would have done without him.

Within eighteen months, her friend was her friend no longer and Pete had become Julie’s second husband.

My sister and I had little in common and did not see each other very often – I was busy with my own affairs, acting as PA to an architect, running the home, bringing up the children

And Julie was busy with her affairs, affairs of a different kind. Affairs about which she told me in great detail on the occasions when we did get together, and always with an element of self-satisfaction which was signalled by an innocent blink of those limpid blue eyes – and even, perhaps, with a hint of pity for me because I led such an uneventful life.

Her marriage to Pete lasted longer, a full eight years. At first he thrived on being perceived as  the strong man about the house, the person in charge, the DIY specialist — and ‘do it yourself’ was not part of Julie’s plan for her life. Nor having children.

But her husband, she confided to me after she had been married for some time, seemed to be getting impatient with her, seemed less willing to indulge her every whim, seemed less enamoured of her helplessness, expected her to take some responsibility.

‘He’s so unreasonable,’ she complained to me. ‘He knew when he married me what I was like, that I wasn’t good at practical things, at making decisions on my own. Said then that he loved me for it, that I was his little girl.’

As I had anticipated, the marriage broke up and ‘old Julie’ – as Ed always referred to her –

moved into a second floor flat on the other side of town and muddled along on her own, inveigling men who lived in the same block to mend her electrical equipment, change locks, put up shelves, sort out her income tax . . . all, it seemed, feeling honoured to have been singled out to help..

And then she slipped and broke her ankle.

Once it was in a cast, she could have moved about in the flat quite easily on crutches and could have cooked for herself, but she managed to look so pathetic, to suggest that her suffering was so intense, that her neighbours started bringing her meals.

‘I suppose we’d better do something about old Julie, too,’ said Ed. ‘We are her only family, after all. Shouldn’t we have her here for supper a couple of times a week until she recovers? I could pick her up after work. How would that be?’

Frankly, I was tired at the end of the day and I found Julie exhausting. I remembered the dummy which she had deliberately thrown on to the floor and which had to be rinsed and returned to her, only to have her toss it out again. Remembered a Barbie doll with a missing arm. Precious books defaced. Endless buttons to be done up, laces to be tied. And later, going to her rescue when her car ran out of petrol, fetching duplicate keys when she locked herself out. It had all been going on for a long time. Too long. I had grown weary of being Big Sister.

But I relented. If Ed, who had had very little contact with her over the years, wanted to do her a kindness, how could I, as her only sister, refuse?

‘Alright, Tuesdays and Thursdays, then, but only until she’s mobile.’

It was agreed that Ed would take her home afterwards while I sorted out the dishes and tidied the kitchen. The return journey should take no longer than twenty minutes at the most.

On the first Tuesday, he was back home after half an hour.

‘Had to help old Julie up the stairs and see her safely into the flat, you know. That ankle of hers is still giving her a lot of trouble.’

On the first Thursday, he was back after three-quarters of an hour.

‘ Front door lock was giving a bit of trouble. Stayed to oil it for her. Poor old Julie is so absurdly grateful for any little thing one does for her.’

On the next Tuesday, he was back after an hour and on the next Thursday, after two hours.

He offered no explanation, but his face did.

After that, I issued no more invitations to supper and I stopped seeing Julie.

He didn’t.

And now you will understand how it happened that, in the middle of last year, my ex-husband became my brother-in-law.

Pamela Williams