Fili and Kili are the sons of Dis, Thorin’s younger sister (there is another brother whom Rateliff assumes is younger still, but remains undescribed and is possibly deceased). As Thorin’s ‘sister-sons’ the brothers therefore fulfil a similar role to Eomer in The Lord of the Rings- as natural male successors to an uncle (in Eomer’s case Theoden, whose son Theodred is of course slain offscreen), and a powerful one at that. Thorin’s demise in his victory might have had them would-be Kings Under the Mountain at the end of The Hobbit, but for their own deaths in defending their kinsman, marking the end of Thorin’s line and the completion of his tragedy. It’s not an aspect which is greatly fed in the book, and their deaths somehow seem more sudden and shocking for that reason; it’ll be interesting to see how the movie will cover this – whether the brothers’ deaths will be similarly unanticipated, or whether we’ll see their doom prefigured heavily in Hollywood-style.
Visually Fili and Kili are hard to distinguish – Tolkien describes both as being the youngest of the Company (a note which seems to have evaded the film-makers, see my note on Ori), with yellow beards and blue hoods. Indeed, both are taken pretty much as a unit, even in official glossaries (although earlier drafts would have had more for them to do, which might have helped distinguish them) In the end Fili is the younger and has a long nose. Both act as look-outs, having keen eyesight (Balin does this too, which either suggests that such a skill does not diminish with age in Dwarves, or that Thorin and Co found a way to keep their eldest member out from under their feet. - discuss), but it’s only in Mirkwood that the two become better distinguished: Fili becomes so tangled in spider web that most of his beard had to be shaved off, and used his better eyesight and throwing skill to land a hook and rope into a handy boat with which the Company cross the Forest River. The grappling hook, we are told, is an improvised tool, made of available rope and some packing hooks from the Dwarves’ gear, and so the hook I made there is an attempt to reflect this. The rope at its end is twist-tie wire braided as best I could and painted accordingly; given the original sculpt is charging with two hand axes, the posture is a tad awkward, admittedly. I also wasn’t half as bold as I’d have liked to have been to make a green stuff nose extension for Fili, so a slight highlight in paint will have to do. Finally, both have a little embellishment in gold and blue on their sidebags, to mark them out in a small way as being a little 'old money'.