Melissa says her daughter, Destoni, is aggressive, violent and a bully. At home, she scares her younger siblings and has chased her sister with a butcher knife. At school, the 14-year-old yells accusations at teachers, gets kicked out of class almost every day, and has even threatened to bring a gun and shoot her teacher and other students.

TELL DR. PHIL YOUR STORY: Problems with your teen?

Melissa says Destoni’s anger-filled behavior started when she entered kindergarten, and she admits that she did not enforce discipline regularly – partly, she says, because she wanted to keep the peace in her home for the sake of her younger children.

On Tuesday’s episode, Dr. Phil implored Melissa to step up and be the leader of the family that they all need. After the show, Dr. Phil speaks with the audience about the importance of dealing with behavior problems as soon as they appear, and not waiting until the child is older.

This episode airs Tuesday. Watch more here.

TELL DR. PHIL YOUR STORY: Know someone with outrageous behavior?

Teen Unleashes Expletive-Laced Tirade On Mom After Learning She’s Going To Treatment