A dwarf with Elvish lifepaths?

My daughter came up with an interesting idea for a character - a dwarf that was taken from his parents and raised by elves from infanthood. He knows nothing about dwarves at all - he has only ever been with elves. I was thinking about giving him dwarven traits but elvish lifepaths. Does that make sense? The ages would have to be adjusted.

Sounds interesting. Go for it.

How would you handle Song Skills and Spell Songs? Elves can do them as they have the First Born die trait where as Dwarfs have the Shaped from Earth and Stone one. Each trait gives there respected races their own version of natural magic, so it’s doubtful that one race could learn the others form of magic. There are some elven lifepaths that do not begin with any type of songs, and the ages really wouldn’t require tweaking as both races are basically immortal to begin with. I would love to read about how this burn plays out.

Hmm… is the trait required to USE the songs, or just to HAVE the songs? The book isn’t clear.
Could the dwarf take those skills, but be unable to actually do anything with them? Or maybe the dwarf might not be able to use them directly, but could still help others with them?

Maybe it works only with Songs that are close to dwarven nature? Like the one for Architecture, Weapon Making or Stone Forming.

The trait is required to learn the skills at all.

I would cook up a lifepath or two for this case instead of using LPs meant for another stock. Or just burn the character up like a monster.

Maybe you could just substitute the normal skills in place of the skill songs? (Demonstrating how the dwarf is learning the same lifepath skills without the benefit of elven magic he is adapting to his world as best as he can). It wouldn’t help with spell songs though.

There’s lots of narrative problems with that approach. How could an Elf teach a Dwarf how to do something like farming, if 50% of even something as mundane as that involves magical singing?

Depends on how magical your skill songs are. I’ve mostly had them work as a normal skill, but with singing added on; Elves farm and craft as usual, but while singing along with the work. The regular stuff gets them the dice, and the singing gets them the benefit of open dice.

Run it like that and the Dwarf can easily pick up equivalent skills and probably a habit of singing as well. But only once he unlocks the power of Drunken Bellowing will he be able to get his open dice.

 I've always thought of the skill songs as rhymes, limerics, and songs that aid the elves in practicing and performing their various skills. (basically a memory aid) they only get the opened ended dice because they are elves, and therefore, have the first born die trait.  
 I suppose that, following this theory, the orphaned dwarf could learn skill songs to performing the elvish skills. But they would not be counted as open ended dice unless the character spent a fate point on luck to do so.  Spell songs would still be off the table, although he could learn them, he couldn't use them for magic. (Just as a human may learn sorcery, but without the gifted trait, he can't cast spells).  This would keep things more in balance points wise as it would still cost two points to open any skill song or spell song, and your dwarf would still have to open the required skills regardless if he could actually use them or not.  Just don't forget about his greed!

See, I always thought it was more like this…

Young Dwarf: “How do you know when to plant?”
Farmer Elf: “I sing to the earth and its reply tells me. There’s a certain chord it makes when it’s ready for seed.”
Young Dwarf: “Oh… How do you know when to harvest?”
Farmer Elf: “It’s in the way they respond to my melody. A ripe carrot will wiggle its leaves as it dances to the song. Too young, and there’s no dance.”
Young Dwarf: “Oh… I can’t sing like you. So how would I know when to do those things?”
Farmer Elf: “Umm… er… I don’t really know! The song’s all I’ve known and all I ever relied upon.”

The songs come from the source material, where the world is created through song. The Elves were granted the gift of knowing some of the lesser songs. See the Ainulindalë, usually published with The Silmarillion.

 So it's a matter of how "magic" is defined in your game then.  What "source material" or magic idiom do you follow, how does elven magic work for you?

Spell songs are exactly as Stormsweeper said (BW, especially the Elves and Dwarves, is heavily rooted in Tolkien). Skill songs in my mind are similar to ritual and work songs. Think marching songs or sea shanties that help people synchronise their efforts. For something like the rope braiding song, it’ll be something where you learn a song and hand motions that go along with the song, and the hand motions are the actions needed to braid cord into rope. Or in ultra nerd terms, things like the litany of boltgun maintenance that helps a Space Marine field strip, clean, and reassemble their weapon while in the deepest of shit.

 So we are of similar thoughts on skill songs, and the first born die trait is clearly required for elves to be able to weave their songs (just as dwarves require shaped from earth and stone to access their natural magical abilities, and humans require the gifted trait to actually use magical.) so the spell songs would never work for our "orphaned dwarf raised by elves" character. He might (depending on the game world's definition of elven magic, which may not necessarily be based in tolkien) be able to use skill songs depending upon the description of  the skill song (I would suggest a case by case basis), "Rhyme of the Gather" ? Sure.  "Rhyme of the Mariner"? Doubtful.  Even if allowed our dwarven friend still wouldn't use open ended dice for these skills as he lacks the first born trait.  Just as he could learn to sing the words of a spell song, in his own dwarvish way, but he could never evoke the magic of those words as he lacks the blessed voice of the first born. 
 Of course, J.J.R.Tolkien and the good folks at the Burning Wheel, never intended for a dwarf to be raised by elves, let alone attempt to learn their ways. But isn't that the beauty of gaming?  LettIng your imagination go?  PlayIng the  role that you want to play, in the game world that you and your friends most enjoy?  Whether or not it is played the way the designers envisioned, the purpose of any game is to have fun.  I bet if she plays her dwarf raised by elves idea, she'll have a blast!

My personal interpretation of skill songs, along with the fact that there are a lot of songs about history, is that elves have extremely poor long term memory about anything that isn’t wrapped up in a song, and so they are continually composing a song about their own lives, so that they can remember what has happened to them. Thus, a skill song is mostly a sequence designed to remind the elf of how to do all the things that they would forget to do otherwise, and also open end the skill due to the magical nature of the song. Thus, I’d rule a Dwarf could learn the song (without the open dice), or just elect to learn the normal skill instead, since the songs contain all the information that are in mundane skills, just wrapped up in a way that elves remember and understand. Of course, this is a very specific interpretation, and may not be suitable for your game, but I quite like the extra alien element it gives the elves.

There are some, like the Rhyme of the Mariner where the elf is singing to the elements in asking for aid (in this case the wind and rope), something I doubt the dwarf could pull off, but it definitely increases the alieness of elves.