8-3-22 I've decided I want this chapter as its own fic, so I've removed most of it here.
Prompt: Do any of the Four play music? How would this change or affect their time in England if they had played an instrument in Narnia, or vice versa?
Chapter 6: Arpeggio
There is a world in which Peter learns the cello, and a world where Lucy learns the pipes, and a world where Edmund learns the harpsichord, and a world where none of the four siblings can play a note.
But they are not this world, and in this world, Susan learns the harp.
The first time they fully explore Cair Paravel and catalogue its contents, amidst dozens of other rooms and treasures, they find a small chamber full of finely-crafted instruments. The strings on many have perished, but the wood and metal are still sound, and Susan finds herself strangely drawn to the deep ebony shape of a harp decorated with elaborate florals.
She gently traces the wooden petals of the large lily that forms the crown, gazes at the empty frame, and resolves to inquire of the dwarves whether any of them recall such craft as may restore it.
They present it to her at Christmas, fully strung and tuned with the kind assistance of Archenland's musicians.
Susan is gentle, but she is also stubborn, and she insists on teaching herself to play. It is rough going, for though she has learned music at school, reading lines on a page is different to playing by ear, and she has never so much as touched a harp before this. Yet she persists, and slowly her persistence is rewarded.
As her skill grows, so too does the depth of emotion she can express with it, and by the time they reach their fifth anniversary of rule, it is not uncommon to find her using the harp as a means to work through feelings. A tense day of court may be followed by the faint sounds of a loud discordant composition, or a letter bearing bad news by a slow sorrowful song. But these are not the only things; joyful dances ring brightly from its strings on days of happiness, and tranquil arpeggios lull the restless to sleep and calm angry spirits.
Narnia rejoices in its queen, and she rejoices in them.
The full oneshot may now be found in its individual posting, Arpeggio.