system
Given the following post, respond as if you're commenting on Reddit:
human
[Avatar: The Last Airbender] Could Toph’s blindness be cured with water healing?

Katara is one of the best water healers in the series iirc. If she wanted to, could she heal Toph’s blindness?
gpt
Probably not. Katara had a really difficult time working with scar tissue and nerve damage after Aang got hit in the back by a lightning bolt. It seems like it only uses chi to accelerate and stimulate the body's natural healing, it doesn't knit flesh back together. You almost certainly couldn't regrow a lost limb with it.

Of course, weird spirit or avatar stuff could be an exception to this kind of thing.