The Letter
It's a short letter that's delivered months after Kuvira has left ZaFou. Only a small fraction of the Earth Kingdom has been united, with most of her and her army's time spent at Ba Sing Se restoring order. There is still much work to be done, when a guard hands it to her, "From the Avatar, O Great Uniter."
Kuvira takes it and opens the envelope slowly, curious. Avatar Korra had not been seen in over a year, still in recovery from her battle with Zaheer. Korra has neat, thin handwriting, similar to Kuvira's own.
Kuvira,
Tenzin's told me how you're helping to restore order in the Earth Kingdom while I'm recovering. But that's not why I'm writing. I never got a chance to thank you for saving my dad's life. I don't know what I would've done if I had lost him.
Thank you.
Korra.
She slides the letter into her pocket, and brings it out sometimes to reread. When she truly takes ZaFou she throws the letter away. It makes her feel like what she's doing is wrong, somehow. Strange and absurd. She burns it in the fire.
Years later, when she marches on Republic City and fires her weapon at Bataar, at Korra the letter weighs heavily on her heart.
And when she receives a letter in prison, announcing that Korra will come to visit her ("Want some tea?" the girl asks with a slight smile) the letter lifts it.