this was a song from Iroh's Story, which was part of a filler episode "Tales Of Ba Sing Se"
I couldn't find the scene in Youtube, but if you watched that scene and not cry, you are not in touch with your feelings and your soul.

Since you probably wouldn't watch the scene, I might as well type the story out.

Iroh's Story talks about him (Iroh, yes he is a man. Yes, he is old. Yes, he is good.) celebrating his dead son's birthday. You see him buy stuff for a picnic and stuff and he helps a bunch of kids. Then you see him on a hill as the sun sets, he takes out a picture of his son, Lu Ten and sets it against a tree. He sets up the typical mourning/picnic food and stuff and he sings the song "Leaves From The Vine"

And obviously he starts crying halfway.

I AM SUCH A SOFTIE. But seriously guys, this scene is so sad T_T it unleashes your inner feels.

UPDATED:
I found it!




WATCH. IT.