They are both about a single parent who seeks revenge on their daughter's rapists. I find broken better than don't cry mommy. But they are both good movies.
Both are Revenge themed movies in which the main lead takes it upon themselves to hunt down the murderer after a loved one dies.
They both centre around suicide and injustice towards rape victims, they also share the social aspects of school girls and vulnerabilities towards sexual harassment and rape, the other main character is their single parent whom is ready to pay revenge to the criminals who led their children to a spiral of unhappiness and depression