The dating scan [12 weeks]

"How long have you two been together then?" After the fifth correction to her technique, their clearly frazzled midwife had evidently decided that small talk would be better than the taut silence that had been spinning out for what felt like hours. Yet at her chosen topic, Molly forgot the insistent pressure on her overfull bladder, paralysed by the lack of an easy answer – what's the best way to introduce your sperm donor?

Of all the silly things Doctor Molly Hooper ever did in the name of love, this had to take the prize…

It all started with yet another of the nurses, Sandra, gleefully showing her ultrasound picture around the break room at St Barts. While Molly normally loved picking out waving limbs and delicate little noses from these grainy shots, the recent run of pregnancies in the nursing team was more than she could bear. Edging out of the room before anyone could bring her in to the conversation, she sniffed audibly, self-pity threatening to overcome her. Missing Tom, her most recent attempt at grabbing on to the normal she thought she wanted. Seeking respectability, in the eyes of her mother, at least, she had ended up with heartbreak, humiliation, and yet one more reason to avoid the world's most perceptive laboratory visitor.

Slamming her way into the cramped office, Molly pulled out her bar of emergency chocolate from the bottom of her bag. With a resigned sigh, she slid the top sheet of her paperwork across the cluttered desk, uncomprehending of its words in her misery.

"I could help you, for once."

"Jesus, Sherlock, how long have you been there?" Her hand pressed to her chest in a vain attempt to still her pounding heartbeat, she eyed the tall man currently perched on the desk across from her.

"Long enough. As I was saying…"

"What do you mean, help me?"

"You have a problem. I can help."

"How could you possibly know what's wrong? Is it the colour of my shirt? No, I know, it must be how I brought my tea back to the office instead of drinking it with the nurses? My hair? Go on, what secret 'she's desperate for a baby' signals am I showing? Amaze me…"

"Desperate for…" The confusion that flickered its way across his face had Molly sinking down into herself, anger rapidly shifting to horror at her own wayward mouth.

"You mean, you didn't deduce…"

"Baby? Nooo… You looked sad. Sad equals problem, so you need help. Friends help each other, a lesson you have taught me over and over again, Molly Hooper. And we are… friends?"

"Yes, of course we are. But, well, obviously, not a thing you can help with this time, though, is it?" Flustered by his arched eyebrow, heat flushing its way up her neck, she blustered on. "Y'know, can't have a baby without one of those 'Dad' things, and I've not got… there's no one… you need to have… God, shut up Molly."

"No matter what you may have heard from my dear brother, I am well aware how babies are made, Molly. And, well…"

At his silence, extending out between them, she raised her eyes, unsure what she would see in them. "And you're offering… sorry, what are you offering?" Meeting his gaze at last, Molly gave a wry smile. Mind palace. It had only taken her seven years, but it appeared that she had, at last, broken his brain. She settled back down to the edge of her desk, confident that this rapid movements of his eyes and occasional twitch of his fingers meant that he was deleting the whole horrific conversation.

Minutes later, when he finally zoned back into the room, his expression softening as he noticed her shy look across the room, his answer had been the single most shocking experience of her life. "So in summary… well. That. If you feel…"

"But you don't…"

"I'm not sure I can handle much more sentiment right now, Molly. This has been quite… well… I'm sure you understand."

"Yes, but… we should talk about…"

"Details, Molly. Now, must dash, Lestrade, case, that sort of thing." And with a gentle kiss to her cheek, he was gone.

The next five months passed in a blur of texts, gaps between cases and unexpected visits. The detective had proved surprisingly keen on… well, the whole process… and Molly blushed to think quite how she would explain their understanding to this relative stranger.

"Oh we're not together…"

"Five months, eight days and… wait, what?"

"WHAT?!"

"You said…?"

"Sherlock, just because we're having this baby together, I never expected… I mean, you have no obligation to me. It's just, you know, help?"

"No, Molly, I don't know. Why don't you explain to me just exactly what part of what I said that day made you think this was just help?"

Flinching at his acid tone, Molly stumbled to put her thoughts into words. "I had a problem, and you… suggested… that you could help. That you knew what I needed and were prepared to offer… for a baby?"

"And what about the rest of it?"

"What rest?"

"How I had come to realise, after some less than subtle help from John, that this terrible confusion of feelings that I had for you was what the rest of you all match to the word 'love'? That I would do anything and everything in my power to make you happy? That I could never deserve someone like you, but that I wanted to try and be the man I see you think I am?"

"But… but… you never..."

"Oh." Dawning realisation spread across his face, chased by a slight twist of amusement. "Mind palace?"

"Seems that way."

"Right. Well. Janet, if we could speed this up somewhat? It would appear that I have a lot to explain to my, erm, to my Molly."

Smiling as she turned to collect the printouts from the other side of the room, Janet felt a swell of the professional pride that had carried her through thirty years of midwifery. Sometimes, all it took was the right question to put even the most nervous of potential fathers at ease…