[The responsibility of their mother's death was a heavy one. When Sokka first found out, he tried to deny the resentment he felt at having his mother taken away for Katara's power. A younger Sokka would have been cruel about it, certainly. He'd have thought their mother died for a 'freak'.

But that little girl with the burns ensured he'd never, ever be able to think like that.]

I don't-- I don't know exactly everything that's different. But, when Katara- this Katara, found her mom and that soldier, she didn't leave when she was supposed to. She tried to protect mom. She used her waterbending.

[Sokka lapses into silence again. There's more to the story, but he doesn't want to say more than he has to. Not when Aang can start putting the pieces together.]