"I was wondering whether you might prefer lemonade?"

Sister Julienne was looking at him kindly. Was she always kind, Timothy wondered? He remembered her coming to their house many times, sometimes at moments that he remembered only as a dull heavy ache, but he never thought of her face without thinking of her smiling or so close to it that it felt as though she was.

He looked around the parlour, at coffee cups and teapots wafted in adult hands. "Have you got some? It's not a problem?"

"Not at all," she said. "Possibly tea and coffee are not entirely to your liking?" She dimpled as he wrinkled his nose. "We have some in the kitchen. I'll fetch it."

Tired from ceaselessly playing the hostess, she was only too happy to busy herself with a practicality. It was only after retrieving the bottle from where it had been left after the last visit of Sister Monica Joan's young relatives that she realised Timothy had sidled into the kitchen after her, almost furtive as he thanked her for the drink. "Sister Julienne, can I go outside and play in the garden? If Dad says it's OK?"

"It must be a little dull being the only person your age here," she said sympathetically.

Timothy shrugged. It had not been entirely dull, but the afternoon had been peculiar, and disappointing. The christening itself was moderately interesting, if only because he and Dad had made a wager in the car, the prize being an extra slice of fried bread at supper, about whether the babies would yell when their heads were wetted; he thought both would, Dad only one. One had cried, the other had whimpered and on the way out of the chapel Shelagh as arbiter decided they should call it an honourable draw where both received the prize. However, after they entered the parlour their cosy prattle ended, swamped by adults who stood like leafless birches, passing platitudes along with tea and cake. He felt ill at ease, on show in the stiff jacket and tie, a briefly acknowledged museum exhibit walked past in favour of more exciting artefacts. He put it down to being the youngest, with the exception of the babies, into which category he had also placed Fred's grandson; yet watching his father, there was something similarly unnatural about his behaviour, the laughter a little too bright, the chatter too enthusiastic. It was as though he was wearing new clothes which didn't fit, and he kept looking around, warily glimpsing at Shelagh when he thought nobody was looking. She seemed quiet, the liveliness Timothy was becoming so used to hidden and jokes they normally indulged hushed by the frequent approach of her former colleagues and sisters.

Bored by conversations in which he had no share, he had found a chair at the side of the room from which he shot occasional pained looks at his father, receiving apologetic glances in return, but also raised eyebrows reminding him it was his own fault. He had been warned to bring his book 'just in case', and had intended to. But it now lay next to the telephone in the hall, where he had left it as he ran upstairs, chased by Patrick's irritable call to hurry up, to collect Uncle David's letter and maybe fulfil the promise to 'talk to Constable Noakes' during a rare occasion when he had every right to be at Nonnatus House. Already several minutes late, he stuffed the letter into his pocket and only remembered the forgotten book when they were half way to Shelagh's. Perhaps inevitably, speaking to Constable Noakes had proved impossible; he was surrounded by well wishers, and while he made a point of beaming hello, saying they needed 'to have a good chat soon', that was as close as they came. Instead Timothy turned his attention to the new challenge, examining clothing more keenly than he had ever done in his life, although his observations increased rather than reduced his puzzlement. His father's grey suit, last dragged out who knew when, was hardly exciting, but he certainly didn't see anything wrong with it. In comparison with the other men, he looked positively dapper, although, Timothy reflected, that might be more to do with his slimmer frame than his clothes; noting the buttons straining across Constable Noakes' chest, Timothy suspected the policeman might not meet Auntie Louisa's standards either, while Bagheera in a suit at all, instead of Cubs uniform or shabby flannels and a cardigan stretched over the beer barrel stomach, was frankly bizarre. It was Shelagh, not his father, he realised, who looked out of place, neither clad in the habit's safety, nor venturing into the nurses' bright vibrancy.

"I meant to bring my book, but I forgot it."

"What are you reading at the moment?"

"The Lost World. It's really great."

"I'm afraid that's probably not in our collection," she said gravely, but her eyes crinkling. "If you wish to play in the garden you are more than welcome if your father doesn't mind, although I suspect it may be a little cold."

She watched him weave his way into the room and past Fred and Dolly to the far side where Patrick and Shelagh were; and the vision made her catch her breath.

It had been strange to see them together for the first time. As it had ever been, she had seen Dr. Turner on an almost daily basis since the day Shelagh returned, both knowing and neither speaking of how and why she had come back to Poplar; until the morning he appeared at her office quietly asking to speak to her on a personal matter. She knew the news he wished to impart before he began and long before she noted the wedding ring which was no longer there. Shelagh she had seen less frequently: an interview later the same day as the one with the doctor about her intention to marry and stay in Poplar, another about her wish to return to work, some social visits to Nonnatus House at the invitation of the nurses and that first tearful meeting, which had ended in an embrace but severed the tie between them. Each time they stood on either side of an invisible wall, which steadily grew though their polite, uncertain friendliness. She felt Shelagh's wordless appeals, yet Julienne could not respond to her, incapable of knowing what they now were to each other or could be, now the young woman was no longer the dearest, most beloved of her sisters. But still the fierce protectiveness burned, as fervently as it had when she feared Shelagh might be dying and begged God to preserve her, even while asking for the grace to accept it if His love for the girl, greater even than hers, was such that He also wished her beside Him. Today she watched as they faced crowds of friendly curiosity together, seeing their shy awkwardness confronted with affectionate, but impertinent, questions and stares. She longed to stand between them now and the gossip, just as she had done at the lunch table when announcing that Sister Bernadette would not return to Poplar and then, later on, that she had and would soon be Mrs. Turner, but did not know how.

In this moment, however, there was no need. For once briefly left alone, Shelagh, taking her turn with little Fred, was sat in an armchair, cradling the baby. From the indulgent, dreamy expression Sister Julienne recognised, she suspected she was singing to him. A shaft of wintry sunshine from the window gleamed on her hair, casting golden shadows over the child and brightening her own pale skin, a young and strange Madonna. And over her hovered Patrick, more startling still. It was not the adoration, so palpable as he watched her care for the tiny scrap of life, but the restfulness, a wanderer who has come home at last. As Timothy called to his father, the tableau shifted in shape and tone. Hands went into the pockets of the Turner men, their expressions animated, while Shelagh gazed up, her face mirroring what Patrick's had been, but sharper, wittier. And then, the picture shifted once more, some riposte drawing Timothy to her, pulling a face at Fred and whispering. She strained to hear, until Patrick freed her by quickly leaning down and extracting the child, knackily taking it in his arms and winding it, just as Julienne remembered him doing to the boy now telling some secret to the laughing woman. Past and present elided and in this moment Sister Julienne saw the future.

"Let her go, Sister," said a voice abruptly. Beside her was Sister Evangelina, her midwife's bag in hand. "Lil Bishop," she added. "Should be fairly straight-forward. It is her fourth."

"I'm sorry, Sister," Julienne replied. "I don't fully - "

"Codswallop," interrupted Sister Evangelina. "You know exactly what I'm talking about and pretending you don't won't make a stroke of difference. She was never ours. She was His."

Julienne opened her mouth to end the conversation, then saw the grace upon her old friend's face and realised the word she had misinterpreted. "God lent her to us for a while and we were blessed," Sister Evangelina said, then softened, quietened. "Genuinely blessed. And this doesn't mean she didn't have that call then as strongly as this one now. But she was never ours, she was just a loan from Him and now He's sent her back into the world with a different calling. And we've got plenty more things to be worrying about at the moment what with her and Nurse Noakes not able to work and all this stuff and nonsense about the building, and you going around with a face like fizz gone flat doesn't help.

"Now, listen to me. Look at her." They both did, at a beatific face, washed clean of the sickening distress of so many months. Julienne remembered when she had seen that face distorted with unhappiness, weeping in the chapel, able only to say how desperately the indefinable, unspeakable pain hurt her. "Look at him. We both prayed that God would send something or a person to support him and comfort him so he could get on with his work. And He has. So let her go, Sister."

They had known each other too long for Julienne to deny or obfuscate. She looked up to the ceiling, her eyes opened widely, choking back the tears, then turned and found them in her sister's eyes as well. She nodded briefly. "Lil Bishop, you say?"

"Yes, Mitre Steet. Nurse Franklin's next on call, then Nurse Miller. I've told them already and Nurse Franklin's changing." She patted Sister Julienne's arm, taking one last look. "Why's she living in some horrible lodging house at the moment?" Sniffing vigorously, Sister Evangelina bustled to the door.

There was an inconsistency, Julienne supposed, between the final comment and the advice repeatedly given, but she pondered the difference, knowing that to reconcile one was to reconcile both. Looking back at the couple, the picture had changed once more, but still it was lovely. Timothy had now vanished, someone else had taken their turn with the baby, and Patrick and Shelagh were standing side by side with Sister Monica Joan, who watched the young woman with gentle fondness. What she said to Shelagh as she touched her face, Sister Julienne could not guess; from the latter's reaction, it had been excruciatingly embarrassing. But Patrick stepped in front of the older lady's pith, deftly moving the conversation and deflecting her next comment upon himself. As she sailed imperiously on, although hardly a muscle moved in either face, Julienne had the strong suspicion that Shelagh was only just suppressing giggles at something Patrick had said. She could not suppress the temptation to smile herself; for this was real life, in its absurdities, humour and understanding, beyond heart-breaking tragedy or gold-tinted, ephemeral romance, however picturesque they might appear. It was Dr. Turner and Sister Bernadette as they had always been, yet more than they had ever been. Despite the beauty of the earlier images, it was now that she wished a camera would capture the mischief in their faces and for the first time, she wondered how it was that she had never seen the inevitability that these two, the lonely widower and the young woman with such capacity for love, would someday find each other.

Whether it was the wish to preserve an image or simply reflecting on missed signs, she suddenly remembered something from months earlier. Glancing out of the window, she saw Timothy listlessly wandering around the garden and running in between the rows of vegetable beds, and returned to the parlour, to rifle through the contents of her handicrafts drawer and then join him in the garden.

He was swinging on the rails of the disused pig sty when she greeted him. "Hello, Sister Julienne," he replied. "Is this where Evie the pig used to live?"

"Ah, you know about that?"

"Yes, Shelagh told me all about it and how Bagheera fed her sponge cake and Akela got a special dress all messy when the piglets got born and how Sister Evangelina pretended that she thought she was horrid, but used to scratch the back of her ears and talk to her."

Sister Julienne chuckled at the memories. She thought she had been the only person who noticed Sister Evangelina's covert petting of the pig and walked by, hiding her amusement. Just as clearly she remembered Sister Bernadette blithely remarking, after an hour kneeling in dirt delivering piglet after piglet and seemingly unaware of smutches of excrement on her face, that, all things considered, she preferred delivering two legs to four. "Yes, that was her sty. Poor Evie." She had never quite reconciled herself to the sow's eventual fate, claiming light indigestion and lack of appetite the day of the ham pie.

"It's a shame you don't have her anymore. Pigs are interesting. Dad says they're much cleverer than they look. Do you miss her?"

"A little," she admitted. "She was one of our more interesting houseguests."

"Maybe Shelagh could bring one back from her sister's, although I think they've mainly got sheep."

"She's going to Aberlour? I didn't know. When?"

Timothy nodded and scowled as he pulled himself up to sit on the top rail. "Yes. Next Sunday. She's going for ages – almost two weeks. And she's going to Chichester for two days next week as well! She says she'll send me postcards, but I wish she wasn't going. I don't think she really wants to. Dad says it's a good thing as it will make her sister happy and it's much more healthy on the farm than in Poplar and it will help her," piecing together what rules of language he knew, he improvised, "convalescence-ing?" Although Sister Julienne laughed, he knew it was not meant cruelly. "What is the word?"

"Convalescing."

"Her convalescing," he said cheerfully. "Actually, I don't think Dad wants her to go either, even though he says he's pleased. He sighs about it when she's not there. I think it's like cod liver oil and he thinks we should put up with it because it's good for you eventually, but it's horrible at the time."

The odd analogy made her smile, but was strangely apt. The small sacrifice moved her; how she imagined the pangs they would feel. "Two weeks isn't really very long. Perhaps you can write to her too." He shrugged. Trying to brightening his mood, she changed the subject. "Now," she said, "I came to find you particularly, because I was wondering if you would like some of this?" In her hands was her block of drawing paper and some pencils. "I remember a charming picture which you drew for Sister, Shelagh," she quickly corrected herself, "sometime back."

"I do that as well!" he exclaimed. "Dad says I say it so often by accident I should just call her Sister Shelagh and be done with it."

She chuckled at this novel suggestion. "And will you?"

"I don't think so," he replied, but he was not chuckling back. "It's a bit complicated." It was so personal a complication, this confusion of guilt and longing which Dad refused to guide him about. He could not bear the thought that he would be disloyal to the precious remnants in his memory, or, worse still, forget them, yet he privately ached once more to use the first word he had ever learnt and to know that he was no longer motherless, not simply loved by his father's wife. Sister Julienne inspired confidences though, confidences of the sort he couldn't share with many people, and slowly he began. "I don't really know what to call her after the wedding. I asked Dad what he wanted, but he said it didn't matter what he thought as the important thing was I'm comfy with it and Shelagh is too and if the two of us wanted me to call her Mum that's OK, but if we didn't that's OK too."

"I think that's very wise advice," said the nun, very quietly.

From the side door, Patrick and Shelagh had emerged, in earnest discussion. They did not touch as they slowly walked into the garden, although their hands were only centimetres from one another. Several times they looked over towards Timothy, at too great a length for it to be checking where he was, yet they seemed preoccupied. She watched the boy's eyes follow them before he spoke again. "I suppose. It doesn't really matter, names, does it? He paused, awkwardly, wondering whether he should continue then plunged forward. "It's not that I don't want to. I really, really do, except I think Granny Parker would be upset. Is that being bad?"

"No." She waited in case he spoke again, then knew he could not verbalise his anxiety. "But the past and those that we have loved in the past don't go away just because something new has begun or we love new people as well, Timothy." In saying words, do we start to realise, she wondered. Is it then we start to understand? "They will not vanish and we don't forget them. Those memories then are part of the happiness now and," she began to feel the truth of the answer now, "you are happy about your father getting married again, aren't you?"

"Oh yes!" The reply was so ebullient she was infected by it. "It's great. It was me who proposed! I wrote it on the wrapping paper round the ring. Dad gave her it, but I wrote the question."

"Yes, I know." She carefully checked herself. "Shelagh told me. She told me it was delightful precisely because it was from you both."

He beamed. "Did you know I'm going to be Best Man?"

"No, I didn't! What a marvellous idea!"

"Yes." He lowered his voice. "Dad thinks I'm just doing the church bit, but Akela and her husband are helping me with the other stuff. I'll probably need some memories from you, about Dad when he started working here in Poplar, for the speech, you know, if you don't mind and have got any good ones."

She could think of many; they kaleidoscoped in her mind. The questions he did not ask about desperate women like Nora Harding, the bills he forgot to send in the first year before the NHS began, the nurses who flourished in the sunshine of his respect and encouragement, the exhausted consultations where he had nothing left except compassion but poured it out. She remembered the energetic young man as he arrived, his intelligence and his passion for healing. He had not been so young, of course, yet buoyed by his clever, pretty wife, his missionary zeal about the NHS and a simple gratitude for being alive and whole after the war, he had seemed so young to her then. Openly, he said, from the start, he did not believe in God or not a God of her sort, he'd seen too much of the worst of man; he believed in science and humanitarianism and the dignity of the welfare state. But he had seemed a gift from God to them, with as deep a vocation as her own drawing him to these forgotten people, blowing away the dusty neglect of the past. One memory, though, was more distinct and this she could not tell the son: she had wiped frost from the door handle as she knocked, watching winter darkness fading into morning grey while she waited for Mrs. Harrison to open the door. Timothy was eating his breakfast with his grandmother, an enormous pair of eyes in a pale face, as she passed the dining room door to make her way upstairs. Four hours earlier she had stood alongside his father, delivering a breech born child. Only this patient pulled her from her sleep. Every day, twice a day for the past two weeks, she had been there, administering morphine injections he could not bear to give, but he could not bear for her not to have. Elizabeth's breathing was slow and laboured, but her face was smoothed from pain, the beginning of the gradual change to sculptured marble. The broken face was Patrick's, sitting in an armchair next to the bed and holding her hand. There was a blanket slung over the arm of the chair, a cushion which might have been used as a pillow and he was still wearing the clothes he had been wearing the previous night; only the removed tie, the disordered hair and the tiny barbs of stubble were different. Julienne wondered, doubted, if he had slept at all. He started as she entered and quickly got up, apologising for his unkempt state and giving a brief assessment, 'Moderately peaceful, little change', before leaving her with her patient and seeing Timothy off to school. The voice was controlled and reserved; it was the resignation which made it so desperately, desperately sad; not a drowning man, but one already dead, hanging impotently in the water. It resonated now, for she had heard its twin only months before, mistakenly thinking then that it was only her own grief which she was projecting into his four short words: 'Crackles. On both sides.' When she saw him in the afternoon he said nothing beyond a report on a patient he wished put on the list for daily visits. Elizabeth died the next night. No, this memory she would not share, but store away where it could not be found.

"Yes, of course. Perhaps we could have tea and lemonade here some afternoon and I will share what I can," she said.

"That'd be great." But Timothy was only half attending now. "They're watching us."

She looked up. Patrick and Shelagh were leaning against the wall, looking at them, he talking at great length while her laughter carried over the garden to them. As Timothy waved and Patrick waved back, Julienne smiled at Shelagh and watched the start of a grin appear on her face.

"Perhaps you should watch them and make them a picture of this," she suggested.

Timothy was fingering the paper; it was rich and velvety. "This feels really different from my paper. Is it special?"

"I suspect that's because you use a different medium," she said. "Do you normally use pencils? I only have this, for watercolours. The paper needs to be heavier, so the paint is absorbed properly."

"Oh, I remember. Mum sometimes did watercolours and she had a special book Dad got her with thick paper like this. Maybe it was because I had the wrong paper that it didn't work when I tried watercolours at school. All the colours mixed into each other and it looked wrong."

"Possibly," she agreed. "I usually sketch out what I'm going to paint with a pencil first, so I have lines on the paper as guides." She saw him look at her in a puzzled fashion. "Shall we sit?" They walked over to a step by the doorway, sat down and she took the pad and one of softer pencils. "May I?" With light, fine strokes she sketched out the scene in front of her. "Here. You put in the lines. The wall here, there the edge of the flowerbed and the vegetable patch, the sty in the foreground, that window, your father and Shelagh here." Now they had turned and were facing each other, still not touching but very close. Instead, he touched the wall, perhaps steadying himself, leaning down as he spoke. "Sometimes it's useful to have people in a landscape; you gain a better sense of relative size. They add perspective," she said, musing over the word.

"I see," said Timothy, although he was not sure he did, and looked around the garden. Although the sun was shining, it was bleak and the garden was lifeless. "There's not a lot to draw really, is there?"

"Perhaps not now. But you can imagine what will be here and sometimes those are the most beautiful pictures, because you can have everything at once. In a few weeks there will be snowdrops over there and after that daffodils and tulips. In the summer there are roses over by that wall near where your father and Shelagh are. And those bushes are raspberries, blackcurrants and gooseberries. Here is where we grow salad vegetables and potatoes. You could even have another Evie in the sty if you wanted."

Tearing off the top page from the block and tucking it into her belt, she left him with a clean page and his slowly unfolding imagination and started to cross the garden to span the other distance. Patrick and Shelagh had looked up so often and sometimes so cheerily while she and Timothy were talking for her to be afraid of disturbing some private tête-à-tête. However, as she drew close to them she felt the mistake. Patrick was asking something, probing, encouraging Shelagh to tell him something, while she looked intensely at him. When she did it was one word, spoken simply, too quietly for Julienne to hear, and with an unwavering gaze.

Whatever she had said had the most extraordinary effect upon him. He seemed profoundly shaken, almost to the point of being incapable of speech. He swallowed and briefly looked away, struggling with some deeply felt emotion and covering his mouth with his hand, perhaps willing the words he several times tried to express to emerge. Faltering, he reached for her hand and only when he grasped it could he finally speak, now fixedly looking at her. "Shelagh, I - ". He stopped and bent over her hand, kissing it, then held it in both of his. "My darling, it would be the greatest privilege and honour." And then, as normality retreated into his face once again, something faintly teasing, almost wicked crept into his smile and finally his voice: "Well, when the time comes, I'll see what I can do."

Julienne wondered if they were a garden of their creation now. The raw intimacy of this moment should not have been seen or heard and she started to turn away. It was too late, though. She had been seen.

"Greetings, Sister," said Shelagh.