During her four short years on the earth, Rosie had changed Molly's life completely, and had undeniably brought her great joy, a lot of laughter and a wonderful, reassuring sense of purpose. She had also, however, managed to confound and embarrass her godmother in a dazzling variety of ways. Loudly trying to draw Molly's attention to complete strangers who were 'very fat' or had 'silly hair' was a common occurrence, and just a fortnight ago, Rosie had locked herself in a toilet cubicle in the Natural History Museum and wouldn't come out until Molly had muddled her way through three verses of 'Let it Go'.

But this was a new level entirely.

This was not happening. Embarrassment in front of people she would never see again was one thing, but Molly wasn't sure she could come back from this.

"We can pretend we've done that bit, Rosie," Molly said quickly, hopelessly. "Let's have some cake."

"No, because it won't be a real wedding otherwise!" their goddaughter insisted.

Molly was about to open her mouth with some kind of attempted counter-argument when she felt Sherlock leaning closer. Surely he wasn't actually going to…? She tentatively turned her head, saw his eyes flicking to hers for a moment before he placed a quick, warm kiss on her right cheek.

Molly felt herself release a huge breath as Sherlock sat back. Oh god - she could actually feel that her heartrate had increased. Just from that! She really needed to give Tinder another go – Sherlock couldn't be right about all of those men.

"No!" Rosie whined, plonking herself down on the coffee table in front of them. "That wasn't a proper kiss! Do a proper one, Uncle Sherlock!"

And then the strangest of things happened. Molly felt Sherlock's fingers find hers on the sofa between them, and then, when she dared look up, he was dipping his head towards hers – just slowly, but definitely moving closer. Dear god – were these really the circumstances where she was finally going to get to kiss Sherlock Holmes? Because a four-year-old told him to?

Time seemed to slow down to an almost unbearable degree.

She could feel Sherlock's breath mingle with hers, smell his signature scent of coffee, toothpaste and the Italian shaving cream he kept in her bathroom. He was watching her as he leaned in, gauging…

"Hello."

They sprang apart so quickly it made Rosie jump.

"Is…everything okay?" the voice queried.

"Daddy!" Rosie cried, running to greet John and wrapping her arms around the backs of his legs.

Molly quickly smoothed down her skirt, tucked some stray hair behind her ears. Sherlock was suddenly equally fidgety, straightening his jacket lapels and cuffs. With any luck, John had walked in just a fraction too late.

"Sorry," John said, staring down at them both and pocketing his keys. "I…I knocked, but I guess you didn't…what's going on?"

There was a look of wry amusement on his face. He had seen the whole thing, and now Molly would have to sell the house, join Médicins Sans Frontières and ask them to post her to some jungle in South America.

As inconspicuously as she could, she started to remove the clips from her hair.

"Uncle Sherlock and Aunty Molly are getting married!" Rosie replied, gleefully.

"Are they really?" John replied, his eyes still very much fixed on his daughter's godparents.

"Yes!" she said. "I did it for them."

John's lips were pulled together in a suppressed smile.

Sherlock cleared his throat.

"Has…has your daughter been fully ordained, John?"

John tilted his head.

"I don't know, mate, possibly," he replied. "You can do pretty much anything online these days, and Rosie is pretty handy with the iPad."

Molly's cheeks were now so warm she thought that Sherlock might soon have a case of spontaneous human combustion on his hands.

John crouched down on his haunches in front of Rosie.

"I think I know what this is about," he said softly, smoothing his daughter's hair. "Is this because Maisie from your class got to be a bridesmaid last weekend? So you need a wedding of your own to go to?"

Rosie frowned.

"No," she told him, before moving on to what was still aggrieving her. "Aunty Molly and Uncle Sherlock needed to get married, but they didn't do it properly, so it won't work."

It was John's turn to frown now.

"Well, they looked to me like they were playing along quite nicely. What didn't they do properly? What won't work?"

Molly gripped the edge of the sofa cushion. Why, mixed in with the crushing mortification, did she also feel guilty – as though John had actually caught them doing something…illicit?

"They didn't do a proper kiss," Rosie complained. "And they won't be able to have a baby until they do a proper kiss!"

She stared at them, as though she was flanked on all sides by complete idiots.

And in fairness, none of the three adults knew quite where to start with that one.

"A…baby?" John asked finally. "Sweetheart, why would they…oh."

Molly saw something pass across John's face, a flicker of sadness and realisation.

"You, ah, you'd like a baby, Rosie?" John asked gently, swallowing. "That's what this is. You want to have a baby brother or sister to play with?"

Molly suddenly felt her heart contract for both of them. They could go for long stretches of time feeling as though they were getting on okay, feeling that between them they were plugging those gaps - and then there would be a sudden, brutal reminder that it would never be quite enough.

Rosie sighed, wrapping an arm around John's neck where he crouched.

"I know I can't have a baby brother or sister," she told him. "But if Aunty Molly and Uncle Sherlock have a baby, I could play with it."

Molly squeezed her eyes shut for a moment, then smiled at her brilliant little goddaughter, smart beyond her years (even if John did still have one or two things to explain about the origin of babies).

"And they love each other," Rosie continued. "So why can't they have a baby?"

John stood up, lifting Rosie into his arms.

"Look, Rosie," he said gently. "Your Aunty Molly and Uncle Sherlock do love each other. But they love each other as friends, and that's different."

"But they live together!" Rosie protested.

Molly felt another blush treacherously start to creep over her.

"No, sweetheart," John said. "This is Aunty Molly's home. Uncle Sherlock lives at Baker Street, remember? In the flat above Nana Martha?"

Rosie pulled a face.

"No, he doesn't!" she said. "That's where he keeps his messy things so Aunty Molly won't mind. He's always here."

"He's sometimes here," John corrected.

"No, Daddy, I saw him in Aunty Molly's bed when I had a sleepover," Rosie insisted. "They were cuddling."

Aaand…that was the point at which a stray meteorite could have crashed through the ceiling and Molly would have welcomed it as her saviour. At the same time, she heard a very strange sound escape from Sherlock; a tiny, agonised moan, like the air being slowly released from a bicycle tyre. Molly prayed that John would at least take the word 'cuddling' at face-value.

John's eyebrows had more or less stuck to the ceiling, as he continued to stare at them.

"Were they really?" he said, eyes lingering on Sherlock. "That is…well, that's…interesting, Rosie."

He suddenly seemed to snap out of it, abandoning his barefaced amusement for his duties as a father.

"But we, ah, we need to let people be private, don't we Rosie?" he said, adopting a serious face. "It's very kind of Aunty Molly to let you sleep over sometimes, and we're very grateful to her, but you mustn't go in her room without asking."

"Daddy, I couldn't ask without going in there!" Rosie retorted. "I didn't know Uncle Sherlock was there, too."

"I know, I know," John nodded. "It's fine. I think maybe Aunty Molly will lock the door next time, and then you can knock. Hm?"

The hm? was categorically aimed at both Molly and Sherlock, along with a deeply self-satisfied smirk.

"Okay," Rosie agreed. "But Aunty Molly said I could have wedding cake before I go home."

John's head swivelled round at high speed, and Molly dropped her head into her hands.

000000000

Sherlock listened as Molly gathered Rosie's things in the hallway, and both she and John finally departed.

He felt slightly as though he'd been tasered.

Hands, fingers, skin, breath…Molly.

He couldn't quite believe he nearly did what he nearly did, but in his defence, it had been a long time coming. Timing and circumstances could possibly have been better, though. He blamed the lip gloss.

When Molly finally reappeared in the doorway of the living room, she was wearing her coat.

"So I…I'm going to go and get those things for dinner," she said quickly, gesturing vaguely in the direction of the outside world.

She was still blushing furiously, still finding it difficult to look at him. If nothing else, it was at least an answer of sorts, to the question he had been struggling with for what seemed like aeons. His own actions – both voluntary and involuntary – had only confirmed it. And now he had an answer, there was no question that he could just sit there and continue his work as though nothing had happened.

"I'll go!" he said, hearing how abrupt it sounded, but doing nothing to correct it.

He stood, quickly buttoning his jacket and pocketing his phone.

"No, you don't have to-"

"I want to!" Sherlock blurted. "I would like to."

He started to head towards the door, moving past Molly and trying not to inhale a guilty lungful of her as he did so.

"But…you don't have a list…"

"Text me the list," he called, grabbing his Belstaff from the coat hook and throwing open the front door.

He made it to the end of the road – out of sight of Molly's front door - before he took out his phone. Fingers trembling, heart thundering, he scrolled to the contact details of the one person who could help him in his current predicament.

Mycroft. How quickly can you bypass marriage notice periods?

As Sherlock waited for an answer from his brother, a text came through from Molly with a short shopping list attached. He scanned it, committed it to memory, and then responded to let her know he might be a little longer than planned. What he now urgently needed to buy, he couldn't get in Waitrose, but he hoped Molly would feel it was worth the wait – both this evening and for the past three years.

And in the long run, if everything went to plan, he strongly suspected that Rosie would like it, too.

THE END