I'm a guy which is obviously different, but I can tell you that SFO is a very safe airport
and wouldn't think twice about sleeping on a row of seats post-security. I've slept in much
sketchier airports, such as CGK, BOG, GRU, at age 17 and never had a problem.

Intl. terminal security officially closes at 2AM and re-opens at 5AM. Maybe you can call
and ask if someone can stay and allow your daughter through if she doesn't make the
2AM deadline?