I have a pretty old dress which got stained with bleach when it was being handwashed. The dress is 100% cotton, and it’s a fairly light lavender color. I’m not sure if it would be better to bleach the entire dress and then dye it, or just use a really dark dye that would mask the bleach spot. I’m also not sure what kind of dye to use. Because the dress is so old, I would feel most comfortable using a non-chemical dye (especially if I am also using bleach).