When Vex is pregnant, it is Percy who takes up knitting.
His lady has never been one to sit still long enough for anything so meticulous. While she walks the woods with Trinket to ease the ache in her back as the child grows, Percy bends over his workbench, constructing a crib, a cradle, high chairs, mobiles, dozens of things that probably already exist somewhere in castle storage, considering how frequently his own parents required them, but it's not the same so he doesn't even bother to look for the heirlooms, he just pieces together heirlooms of his own. When he has just about run out of things to build for the expected new de Rolo, he comes across a book in the library detailing knitting stitches.
Whitestone is an awfully chilly place for something so small, so defenseless against the winter, he considers.
Cassandra is of no help. She swears no knowledge of the last resting place of their mother's old knitting needles, nor has she ever had an inclination to take up the hobby herself. Undeterred, Percy peruses the knitting book and compiles a shopping list.
Percy walks into town one day while Vex walks in the woods. At market he finds a farm wife who spins wool finer than most, and he buys an armful of her softest yarns. With them he brings home a plain pair of needles, sits down with the book, and delves ever deeper into his repertoire of colorful curses as he tries and repeatedly fails to interpret the casting-on instructions.
On the dozenth try, something clicks. Stitches appear by some arcane process on the needle. With a deep breath, he turns the page and considers the process of extending them another row. To his utter relief and secret delight, that part turns out infinitely simpler than the cast-on, and hours fly by as the fabric lengthens, row by painstaking row.
He's not sure what exactly he has made, at the end of it, when he finally decides to tackle the page on binding-off. Surely infants have little use for a potholder. Perhaps it can be sewn on something as a pocket? Have infants a use for pockets?
Vex'ahlia finds him pondering pockets. He expects her to scoff at his shabby first potholder, but she beams. This intricate, if somewhat lumpy and off-centered, web of woolen loops is apparently as fascinating to her as any gadgetry or trick arrows he's ever produced. His would-be pocket disappears with her, he assumes to some nursery-related purpose.
Percy sits at the workbench, turning one needle over in his fingers. It's really a very crude thing, merely a rough wooden dowel given a pointy tip. Too large for the fine thread he had acquired. With a needle of a smaller circumference, he might work stitches closer together, better suited to shield a helpless child from cold winds.
He turns to his forge, rummages through scraps of metal. His eyes light up at what his hands find: a small bundle of hollow steel shafts. They were to become arrows, eventually, if he could ever get the weight and balance of them right for Vex'ahlia's needs; their hollow centers would have been filled with trip wires or poisons or -
Arrow thoughts fly directly out of his head. He can no longer recall what exactly he had been thinking of doing with the shafts before he realized these abandoned thin pipes, polished smooth and given a proper point, will make perfect knitting needles. Vex will need arrows again someday, but for now, Percy has wool tinkering to do.