Every night she lights two candles. Nobody else knows why. She'll stare at them, and the island wind will swirl around them, a gentle zephyr, making the flames dance, bringing tears to the girl's eyes.
It's her secret, her own, just between her and the breeze, the breeze coming from the island, their island, rich with the scents of coconut and the wide blue sea. She breathes deeply, her eyes becoming watery, until finally she can't hold it in and she starts sobbing for her lost two.
"I'll never forget you," she murmurs fiercely, the same every night, but her whisper never loses its passion. "I know you'll come back."
The night before she leaves, something different happens. The wind speeds up, no longer a gentle zephyr, as she recites the letter she wrote, her eyes glazed as she remembers the bottle floating out to sea.
Her tears flow down her face, and she chokes out the last words, blinking determinedly. "...one destiny..." she manages finally, and the wind rushes up to a roar, and the flames are snuffed out. With a sigh, she reaches for the matches, but the box is empty.
Distraught, she leaves the candles, hoarsely whispering, "I know you will!".
That night, the first one after their return, she can't help but think it's too good to be true. They've returned. The zephyr of wind ruffles her hair as she sits on their island once again, Sora sprawled on the branch next to her, Riku leaning against the tree with that same thoughtful expression.
She remembers her candles and her promise, and she starts to cry. Concerned, Sora sits up. "What's wrong, Kairi?" His blue eyes are wide, and Riku is gazing at her, as she sobs. There is a silence, but then she finally stops crying.
"Nothing," she says, smiling. "I knew you'd come back."