My little girl, who is a grown-up was digital harassed on a site and name is being criticized, labeled and posted in a specific gathering. How can be treated this?

My little girl, who is a grown-up was digital harassed on a site and name is being criticized, labeled and posted in a specific gathering. How can be treated this? Who would I be able to contact? This happened do to desire. Things got quite awful. Indeed, even the manager sat idle. Would you be able to sue somebody on the web in a very surprising state?? Any data is enormously valuable.