Melissa says her daughter, Destoni, was the perfect child until she started kindergarten, and that’s when she says things took a turn for the worse. She says the now 14-year-old is disrespectful, violent and aggressive – both at home and in school -- and she’s been suspended nine times.

TELL DR. PHIL YOUR STORY: Is your teen in crisis?

“On two different occasions, Destoni came at both my babysitter and my older daughter with a butcher knife,” Melissa says. “On a good day, Destoni will tell me to shut the hell up. On a normal day, Destoni will tell me to shut the [expletive] up.”

Melissa’s mother, Michelle, agrees that her granddaughter is out of control with a “major” attitude. “She’s uncontrollable and she’s a monster,” she says. “She just recently yelled out that one teacher had chlamydia.”

WATCH: Teen Tells 'Dr. Phil' Producer To Get Camera 'Out Of My Face' Or She'll 'Destroy' It

Desperate for help, Melissa reached out to Dr. Phil. “My biggest fear is that Destoni has threatened to shoot up the school, multiple students and teachers,” she says.

Hear more of their story in the video above. And, Dr. Phil has some questions about Melissa’s parenting.

On Monday’s episode, hear from Destoni. How does she behave with Dr. Phil? Plus, on Tuesday, Destoni comes face to face with a group of her peers. And, will she take Dr. Phil’s help? Check here to see where you can watch.

TELL DR. PHIL YOUR STORY: Hopelessly in need of Dr. Phil's help?

'Inconsistent Parenting Creates The Most Resistant Behavior,' Dr. Phil Tells A Mom