Death by bullying?

Here is a semi-hypothetical question, if a tween girl who is an immigrant is picked on and bullied because she is not familiar with American social norms etc. The bullying usually happens to and from school away from the control of the school, and the incidents that happen on school grounds are hard to substantiate due to the language barrier and being out numbered. When is morphs into cyber bullying and the girl bullied commits suicide was there any crime or wrong doing done? Could the girl’s parents sue, and if so, who? Do they just have to suck it up that their daughter could not withstand the onslaught of the “mean girls”?