The longer that Sherlock remained in hospital, the more withdrawn he became. He seemed oblivious to John's presence much of the time, responding to his questions with either non-commital grunts or silence. He refused to let John help him research Magnussen, telling him that he didn't trust him not to release information to Mycroft about what he was up to, and he continued to refuse John access to his medical records or any information related to his treatment.

After all those of weeks of being so involved, the hours spent waiting by Sherlock's Intensive Care bed, analysing his charts, researching treatments on the internet, John felt entirely redundant.

He found himself sleeping later and later in the mornings, postponing the time when he would go to visit. And each time he walked into Sherlock's room, it was with the hope that he might find Sherlock in a contemplative mood and regain some of the intimacy of that night after he had regained consciousness. As the days ticked on, John began to think that he had imagined the whole thing, from stress and sleep deprivation and projecting his own desires onto the situation.

Sherlock would barely grunt at him in acknowledgement some days, furiously clicking away on the latest iPad that Janine had smuggled into him, this one secreted into a huge hardback book entitled, 'A history of British fashion from 1920 to the present day.' John very much suspected that the security guards outside were aware of what he was doing, but simply couldn't be bothered to keep confiscating devices when Sherlock obviously had access to a steady stream of them. It had been a game to start with, but then it had just started to become dull. Besides, Mycroft was away and while his attention was diverted away from his little brother, everyone had relaxed their guard a little.

John even got a, 'Good morning, sir' from the security men when he arrived, and a 'Good night, sir,' when he left. He wondered what they thought about all day, standing there on guard like a pair of sentries, one on each side of the door. Occasionally they would check their smart watches, check in on their ear pieces with a third and maybe even a fourth man at some unknown location, but close enough John was sure to be within running distance if the attempted assassin came back. Sometimes John wondered who Mycroft wanted Sherlock guarded from - not Mary surely, so Magnussen? Or was he protecting his brother from himself, preventing him from leaving hospital? And did Mycroft really believe that two men in suits would prevent Sherlock Holmes from escaping if that was what he wanted to do? John wondered if that wasn't all part of Mycroft's game plan - to irritate Sherlock into getting well. If so, then his plan seemed to be working.

John's days visiting Sherlock were very long and very dull. Part of him was happy to just be there, sitting with Sherlock , watching him work. A larger part of him was getting increasingly frustrated at not being allowed to help. Sherlock had put him on 'goon watch' as he called it; getting him to cough or clear his throat every time one of the guards moved, or looked towards the door. But other than that he was stuck reading the paper or doing the crossword and there were only so many sudoku puzzles that a man could complete. Especially when Sherlock Holmes could complete them in less than a twentieth of the time that you could. Sherlock didn't even like sudoku. He only did it to prove his superiority, reaching over and pulling the book out of John's hand when he'd been sitting there chewing the lid of his pen for the several minutes, stuck on a particularly tricky part of the puzzle. Sherlock would then complete the entire puzzle in lightening speed before handing the book back to John and berating him for chewing the pen.

'Did you know that you can get bezoars of plastic from chewing pens?'

'That's rubbish and you know it.'

'It's perfectly true, I assure . They get trapped in with the hair from hair-chewers and can form a ball in the stomach which eventually leads to gastric outlet obstruction. They found one that was ten centimetres in diameter in the stomach of a twenty-three year old in Krakow in 1983.'

John frowned at him, 'Why are we talking about hair balls?' He asked. 'And why did you finish my sudoku for me?'

'You appeared to be struggling. Besides isn't that the point? To complete it?'

'It's meant to be entertaining, Sherlock. It's the challenge that's fun.'

'But the point is to complete it.'

'No, the point is to ENJOY completing it.'

Sherlock looked baffled. 'Look, it's like a case,' John explained. 'The easy ones aren't fun, are they? You don't like those. You like the ones that are a challenge, the ones that you have to work for, where you have to piece together the information slowly, where each revelation is a new delight, where you slowly build on it and build on it until you reach the - climax.'

John bit his lip and looked away, not sure whether he wanted to laugh or crawl into a corner. How has he not realised this before? Sex, it was like sex. That was what a case was like for Sherlock; the slow circling round, the gradual build of information, getting deeper and deeper into it, approaching the solution, backing off, trying it from another angle and then that moment of triumph. John had thought that Sherlock was asexual until the last few weeks, until his illness had made John seen him in another light, but he was wrong. Sherlock got his kicks from the deductions, from the work, but if he could persuade him to transmit that into something more physical then maybe, just maybe...

John looked up to find Sherlock staring at him with a strange expression on his face. His eyes were more green than blue today, iris heterochromia came the thought from nowhere, but in this moment, Sherlock's irises were just a narrow a rim around a pool of black. Sherlock's pupils, normally constricted from the opiates that he was on, were dilated and wide. He looked - no, it was impossible - his pupils made him look as if he was aroused but how could he be. Was that really all it took? John talking about the work, John understanding that work for him was like sex, that that was what he got his kicks from? Could it really be that simple?

And then John saw the slow smile on Sherlock's lips, and looked down to see a finger brushing against his hand where it lay on the bed, just a finger, barely touching. John cleared his throat, 'Sherlock,' he started to say, 'I need to ask you something. Do you-'

And then they both jumped at a loud knock on the door. 'Time for your echo,' the nurse said, indicating to the porter waiting outside with the wheelchair that he should come into the room.

'Could you just give us a minute?' John asked, desperate that he should hang onto this opportunity, this moment of closeness. Dammit what was it with all these interruptions?

But Sherlock had blinked and his pupils had returned to their normal size. 'A minute for what?' he asked, frowning at John and looking genuinely perplexed. He flung back the sheets and swung his legs out of the bed on the opposite side to John, checking his watch as he did so.

'Besides, don't you have an appointment of your own?' he asked John.

John frowned, momentarily confused.

'Mary's next ultrasound scan is in ten minutes in the maternity block,' Sherlock continued. ' I'm sure that you don't want to miss it. Second floor, ultrasound room two. It will take you precisely seven minutes to walk there. Now chop, chop or you'll be late.'

'I'm not going,' John said. 'I've already told her that.'

'Of course you're going, John. Don't you want to see what your child looks like? Let's hope that it has Mary's brains and not yours for a start.'

John pulled his hand off the bed, gripping the arm of the chair in irritation at this sudden flip in mood. Less than three minutes ago, Sherlock's hand has been stroking his and now he wanted him to go and see Mary's scan? What the hell was going on?

'Since when were you on Mary's side?' he asked in irritation, trying to ignore the interested looks of the nurse, the porter and the two security guards who were waiting outside the room the score Sherlock down to the Cardiology department.

'Besides,' he whispered, turning away from them to face Sherlock, not wanting them to overhear his conversation. 'How do I even know that it's mine?' There, it was out there, the thing that had been circling round and round in his head ever since he found out the secrets that Mary had been keeping. He has finally said it out loud to another human being, he was just a little surprised that that someone was Sherlock.

'Oh grow up, John and use that thing you keep between your ears and call a brain, ' Sherlock said impatiently. 'Of course the baby is yours.' Sherlock reached into the cupboard beside his bed, pulled out a folder and threw it at John who caught it before he realised what he was doing,

'What's this?' He asked stupidly.

'DNA report. Conclusively proving that the child that Mary is carrying is yours.'

John just stared at him.

'Look at it, John. The baby's DNA retrieved from Mary's blood; your DNA retrieved from the toothbrush you left in the bathroom at Baker Street - I'm slightly disappointed you didn't notice the switch, by the way but then you never were that observant. The DNAs match. The baby is yours. Now off you trot to see that scan.'

'You really think it's that simple?' John asked.

Sherlock sighed. 'Make it that simple, ' he said, firmly. 'The baby is your child. If you want to be a part of its life, then I would highly suggest that you start now. I'm told that perspective parents generally find watching their unborn foetus on a small screen in grainy black and white images both reassuring and pleasurable.'

'And if I prefer to go to your echo - with you - rather than watch a blob on a screen?' John asked, aware that his voice was shaking slightly, although whether with emotion or after he couldn't have said.

'Then you would be lying to both yourself and me about where you really want to be, ' Sherlock replied. 'And it is a decision that you will almost certainly regret in the future.'

Neither of them seemed prepared to break eye contact first, until finally Sherlock said, 'Please, John. Just go. Not for Mary, or yourself, but for the baby. Because this whole situation really isn't her fault.' He watched John's face intently, before adding with just a hint of a grin, 'Besides, with your combined sets of genes, she's going to need both of her parents behind her, don't you think?'

John stared at him for just a minute longer before nodding just once, and them before the could change his mind or think about this too much, he stood up and walked out of the room without looking back. He was halfway to the scan department before he realized that Sherlock had said she. Did he know? From the DNA report that John himself had only skimmed did he know that the baby was a girl, or was it just a turn of phrase? Mary and he had agreed before the first scan, before his life had fallen apart, that they wouldn't find out what sex the baby was until he or she was born. But this was Sherlock Holmes, nothing he said was by chance. If he has said she then it was for a reason. Its was because it was the truth. And now John knew something that Mary didn't. They were going to have a girl; a daughter. Now there was something.

John glanced at his watch and broke into a run down the stairs. If he was going to have to go to this bloody scan, then he wanted to make sure that he saw all of it.

...

Mary was already in the room when he entered; even Sherlock Holmes hadn't been able to deduce that the sonographer would be running early. His wife was lying on the examination coach, top pulled up to her bra line, a piece of white paper tucked into the waist band of her maternity trousers to protect them from the ultrasound gel.

She looked up in surprise when he stuck his head round the door, scanned his face for a moment as if to check if his intention was to pick a fight, and then her face broke into a smile, that lightening fast grin that he loved so much. 'Well don't hover on the doorway,' she said. 'Come in, if you're coming.'

The ultrasonographer told him to have a seat and then turning to Mary asked, 'ready?'

Mary nodded and John saw her wince as the cold ultrasound jelly on the probe hit her abdomen. Then he saw something else, a tiny movement on the screen. 'Baby's waving at you,' the ultrasonographer said, and then as she pressed a few buttons on the screen, the blur turned into a hand. His child's hand. John choked back something that was close to a sob and looked at Mary to see that her eyes were wet too. She squeezed the hand that he hadn't even realised that he had placed over hers. 'Our baby,' she said. And so it was.

He watched his child move on the screen, watched the sonographer scan her head, her heart, her stomach her face, her legs. Her, he was already thinking of her as a girl, but when the sonographer asked them if they wanted to know the sex, Mary said 'No!' more quickly than he could say yes. But he had seen it, the classic 'hamburger' sign of female genitalia. The sonographer looked up at him as her probe lingered and he winked at her and grinned to show he had seen what she had. 'Mary's the boss,' he said. 'If she wants to wait to find out then we'll wait. As long as the baby is healthy, that's all that matters.'

'The baby looks perfect,' the sonographer assure him. 'Now did you want some pictures to take home?'

Five minutes later and they were walking out of the room, Mary still looking at the grainy black and white pictures of the baby. They walked together to the corner of the corridor, then loitered awkwardly, neither of the, sure what to do next. John felt as he was torn between two alternative realities. He felt an odd allegiance in that moment with Mary, the mother of his child. There was an almost overwhelming biological need to be with her and his baby. He wanted nothing more than to wrap his arms around her and hold her tight, the baby safely cradled between them. But there was another Mary too; Mary the liar; Mary the assassin; Mary who had shot his best friend and nearly killed him. He wished that he could divide those two, but he couldn't.

He realised that he was facing her, and pushing doubt aside, he did what felt right - wrapped his arms around her and held her tight.

'We made a baby,' he said into her hair.

'We did,' she said, hugging him back. 'Now are you going to take me out to lunch and feed me? Because me and the baby are both starving.'

'Mary -' he started, pulling back to look at her.

'I know John, I know,' she said, looking down at the pictures still held in her hands. 'But just for one day can't we pretend? Can't we at least go out for lunch and talk about this little one's future and how much of a handful they're going to be with our combined genes, and not think about what's happened?'

John looked down at the picture, hesitated for a second, then nodded and grinned at her. 'Can't have my child starving can we?' he said, as he draped an arm around her shoulder, just as he used to, and she put her arm around his waist and they walked out of the hospital like that. Arms around each other, and their baby safely held between them.