It all started one day when River caught Kaylee knitting up a nearly unidentifiable, knobbly grey something-or-other that was to be gifted to Simon when completed. She was absolutely fascinated with the process and immediately demanded to be taught. Somehow, apparently, it had been skipped over in her overzealous childhood learning as well as all that mind-breaking assassins training she'd gone through.
Kaylee was tickled pink by being able to actually show River how to do something for once, and it wasn't long before they could both be found feet dangling from the hanger and chattering away, River stitching up some sort of intricate spiderweb lacework while Kaylee continued diligently on with... River still wasn't sure, possibly a sweater. It had a red stripe in it now.
If Kaylee minded that her pupil had picked up the craft in a day and far exceeded her teacher's abilities within two, she definitely didn't show it and was more often than not seen praising River's latest trick. Every now and then River would have what Kaylee was starting to think of as 'an episode' and she'd have to carefully extract the poor girl from a knotted panic induced mess. It became something of a game after that, to unravel River and distract her troubled mind with silly nonsense.
That was how Inara had found them one day, both tangled in a heap and giggling uncontrollably. It wasn't all that long before Inara got sucked in and joined them with an ancient shawl project she'd very nearly forgotten. Of course she'd learned the craft at the academy but she never really expected to use it much in her current very-nearly-a-pirate lifestyle.
With enough badgering Wash got Zoe to try to learn with him. Between Kaylee and Inara showing them the ropes they were both working on simple projects in no time. Nobody really knows how or where, but Wash somehow found some ungodly hot pink yarn and was making a hat that was at least two sizes too small. Zoe stuck with a simple beige scarf and while it was nothing over complicated she crafted it well.
The Shepard took up the needle next, diligent and patient, enjoying the time to relax and listen to his small, somewhat special flock. Occasionally he'd come up with some sort of bizarre anecdotal story about wool or something equally baffling. Nobody really knew where he pulled that sort of knowledge out of but it fit in well with the relaxed nature their little knitting group had formed.
Jayne and the Captain would float by occasionally. Jayne would attempt to mock Wash for bein' girly (while carefully avoiding Book's eye) while Mal sat back and looked smug, not agreeing outright, but not disagreeing either. That stopped fairly abruptly when River non-too-gently shoved a ball of yarn and a pair of needles into Jayne's hands and said something indecipherable and cryptic that nobody could catch more than "cunning" and "ma" out of.
Whatever she had said got even Jayne to try his hand at knitting much to pretty much every body's shock. After five minutes of grunting and stabbing the ball in frustration he eventually shoved the whole mess into Simon's hands as the doctor failed entirely to stealthily figure out what exactly Kaylee was making already.
Mal got a pretty fierce glare from River and a mostly benign look of amusement from Book as he slunk off to the cockpit to avoid a similar fate to Jayne (someone had to drive the gorram boat anyway) and Simon settled in next to Kaylee who had just started adding a blue stripe to the monstrosity.
When he asked what she was making she gave him a curt, "Never you mind!" followed by a shy, "Do you like it?..." Unsure how to react Simon cast about desperately, hoping for a clue. Inara was looking down at her work politely but still managed to convey laughter, Zoe was being particularly stone-faced while she watched as Book showed Wash how to stop mangling his hat by loosening his stitches, and River was muttering "Don't mess up, don't mess up, don't mess up." under her breath while she flawlessly churned out a scarf that looked suspiciously like it had a DNA helix on it.
"It... it's really nice." Simone stumbled. He could always figure out what the hell it was later... for now, Kaylee's gorgeous smile told him he made the right choice.