AN: Standard Disclaimers Apply.
The light film of soapscum gave him just enough purchase to slowly lower himself into the empty motel tub. Tossing his trousers out of the way, he stretched over the side for the medical kit. Sherlock growled as he pressed his injured leg into the side of the tub digging for the sutures. The phone only Mycroft could access gave off a clear precise C flat as he dumped a third of the alcohol over the deep cut. Twenty-three stitches later, Sherlock struggled back to his feet, walking into the dingy bedroom. He forced himself to eat what was left of the takeaway before checking the phone. It was usually just a text of coordinates and basic details of that operation. But not this time.
It was so bizarre his brain went on autopilot. "I'd say twenty weeks judging by the spine length, limb and digit development. No obvious physical abnormalities or defects. Position is wrong for determining sex of the fe-" Sherlock snapped out of it at that word. "Why in the world did you send me this Mycroft?" he swung his arm away in shock only to snap it back determinedly.
Small bits of text ran along the top of the image, two quick taps had it zoomed in on the left corner. "2 p.m. three days ago. Patient: Watson, J." Sherlock frowned. "It can't be Jane, she wasn't with anyone five mon-" precious memories of that awkward night broke through his mind palace as he stumbled back. "I've only been gone for seventeen weeks... Oh God, Jane."
He set the phone in his lap, smiling weakly at the image. "Just as strong as your mother." He absently traced the baby's back as he committed the picture to memory.
AN: I've been reading a lot in this category and the HP crossovers and I've only seen this twist 3 times, which is shocking considering the number of genderswap fics that are in this fandom. There's only one where fem!John is pregnant and its leaning to a triangle of her and the brothers.
