Hope. Determination. Optimism. Those things could get them through the day, but nighttime in Ba Sing Se was a different story. At night, Aang would stare out the window of their apartment for hours, wondering if Appa would ever come back.

It wasn't fair. Appa had always been with him, even for the hundred years he was trapped in the ice. Appa was all he had left of his old life, as long as they were together he didn't feel like the last Airbender.

Now he really was.

Katara would always find him still awake long after Toph, Sokka and Momo had gone to bed. Some nights she would easily lift his spirit with words, help him make more "missing" posters. Other nights, when he was too upset to talk, she simply held him.

"You're not alone, Aang. Even without Appa, you're not alone."

And he would smile, because when all was said and done he knew she was right.

I'm not alone as long as you're here with me.