I have expressed to my kids that the age of the electronic footprint is much different than what we grew up with. Employers, police, governmental officials all search social media for different reasons.
At the least she should restrict her twitter account so no one can read it except for those that she allows to follow her.
Bimini is correct, however. As society deals with integration of social media in controlled (school, work place etc) environments there are rules and norms to be followed. Good lesson to learn young, lord knows I did not