Father had many strange habits, Kili remembers, but that one was among the oddest. Father had always been an odd one, hardly dwarvish by look or talk; many wondered why their mother chose him, seemingly frail and pretty almost like a woman (or an elf). They were different like moon and stone, father and mother, and yet they lived a life together, shared food and bed and toil, and mother bore with all of his quirks, and, indeed, with this one.
She rarely smiled, their mother, she was strong and underneath the hard shell she had an even harder soul, for she truly was one of Durin's seed. But, sometimes, she smiled.
It always looked like a crack in stone, cold and hard and somehow disconcerting. But father—he used to kiss the smile on her lips when he thought there was no-one around but the two of them, and smile back like their mother's smile was the greatest, purest, gem in their treasury.
Their mother was a wise woman; she brought them up and taught them to obey when deference was due and to bare their swords when their honour called for it. She was stern and unbending, and she was a strong one; she never shed a tear when father died.
She never taught them how to smile, too, Fili and Kili; the smiles on their faces were the sole inheritance their father left behind.
oooooooo
So when they take the hobbit on a journey, Kili can't help but laugh. Mother would have broken Baggins between her fingers, he thinks, like a twig that's no good for building or mending, no good even for starting a fire. The hobbit's ridiculous and laughingly faint-hearted, not a true man if Kili ever saw one. He makes for the lucky number, though, so Kili thinks nothing of it.
And when the hobbit proves brave, Kili thinks nothing of it, too; Baggins is just a bit more of a man than it seemed, at first. It's the way it should be, no more, no less: men risk their lives for the sake of others, then have a good beer and a laugh about the mortal danger they'd faced. This is a man's way to live and to die, and Kili would die for Bilbo—like he would all of his brothers in arms; and he's—satisfied to know the hobbit's worth it.
And when the hobbit proves cunning and resourceful, Kili can't help but respect him further, because that is something not frequently seen among his kin. But that's not what makes him most glad that Bilbo came on a journey, after all.
oooooooo
When the hobbit smiles, Kili can't help but remember his mother, the way she used to smile, like stone and steel, and the way father looked at her as if that smile were a treasure.
Baggins' smile is anything but. It's neither secretive nor hidden, never guarded or cold, the way treasures are; it is on display, open and free, for each and every single one that can see it. Look if you will, take if you want, it says; and it is soft, like summer and peaches and late afternoon sun, and that is something Kili's people neither truly understand nor crave for. Dwarves dwell in the dark, they wright steel and chase the cold away with fire, hissing and spitting and roaring; never the homely flame of the cozy mantelpiece Bilbo misses so. Mother would have broken this weak one, this soft one between her fingers so very easily.
Only Kili understands that look on his father's face better now, he thinks; because Bilbo's smile is nothing but a treasure, dazzling and precious and, somehow, inexplicably beautiful. It lights up the room like few gems do, and it shines like the famed Arkenstone Kili had never seen with his own eyes in his short life and only heard legends of, so many legends and memories.
And dwarves, Kili is forced to remember, are very jealous of their treasures, when those are put on display.
It hurts to look at that smile, like a diamond lying in the dust, and Kili wonders if he could probably take Bilbo's face in his palms and kiss away the sadness that eats at him, until everything that is left is the glow that surrounds this silly little man with a big, big heart and a dizzyingly beautiful smile.
They nearly die, again; and then they don't, and Bilbo laughs, a bit uncertainly, and the smile lingers, and when presented with a treasure, no dwarf can resist.
Gemstones are cold, but Bilbo's smile is warm on Kili's lips.