I might sound really silly here, but I'll do it anyway...
My father is half Bangladeshi, so I have dark hair by relatively pale skin. My mother is fair. When I was about 13 people at school started noticing my facial hair and so my mother told me about jolen and got me to bleach it like she did. She never told me about any of he other options and I sort of wish she had, because I hen got really paranoid about just having a blond moustach, which didn't show up on my mum but did on me. I was also sure that it made that area of my skin lighter than the rest of my face, although that could have just been paranoia as well!
Basically what I'm saying is, I know your daughter is 19 so is probably well aware of other options, but maybe she is nervous of tying them and/or being able to afford them. Maybe she would reall appreciate talking it through with someone she wont feel embarrassed about it with.