By Andrea Lucia

BOSSIER CITY, LA (CBSDFW.COM) – Ever so often, Jessica Morton pulls out the stack of tapes.  She’s saved every recorded moment of her daughter’s life.  She’s kept her drawings, her poems, even her old toothbrush.

“I’m sure I’ll throw it away one day, but it was hers,” she said.

Danielle Cox was an artistic 15-year-old freshman in Bossier City, Louisiana, who stood out from the crowd.

Still, her parents say they had no idea she was being bullied, until a sheriff’s deputy woke them one morning with a knock at the door.

“It shocked us both. She was supposed to be in bed,” said her step-father, John Morton. “Evidently, they had information she was wanting to harm herself.”

Danielle, he said, had tried to overdose on Tylenol.

“I was scared to death, so I grabbed her up and took her to the hospital,” said Jessica.

That night, Danielle’s phone records show she’d received 150 text messages urging her to “end it all.”

“I won’t miss you,” they read. “You’re not important.”

Her parents later learned those messages all came from one classmate, who had used a website, to overwhelm Danielle’s cell phone with texts.  The web program made it seem like they all came from different numbers.

“She thought it was a hundred or so people sending her those texts,” said her mother.

Danielle was committed for psychological treatment and returned to school three weeks later.

“We thought everything was going good,” said John.

But on May 20 last year, her mother and a family friend realized, the torment had never ended.

“They found her hanging in the closet,” said her step-father.

No longer limited to the schoolyard, bullying is gaining new and more vicious forms online.  Government statistics show more than one in three young people have experienced cyber threats online.  And more than 25 percent of adolescents and teens have been repeatedly bullied through their cell phones or the internet.

“I know it’s probably going to be worse in the future,” said Hood County Sheriff Roger Deeds.

This summer, Deeds made a controversial move, arresting two middle school girls for creating a fake Facebook account to pick on a classmate.

“A lot of people are looking at us to see how this goes because there haven’t been a lot of cases like these,” said Sheriff Deeds.

Dallas Police say they have also investigated cyber bullying, using search warrants to seize suspects’ phones and laptops.  The one advantage they have? Everything posted online leaves a record.

In Bossier City, sheriff’s deputies followed the trail to 17-year-old Jason Thomas, who they charged first with ‘cyber bullying’ and later felony ‘criminal assistance to suicide.’  The Mortons, meanwhile, have sued the school district trying to force changes in bullying policy.

“Mandatory training for teachers, mandatory,” said John.

They’ve also started an organization, called Smiles for Danielle.   Their mission is to encourage people to be kind to each other, just like Danielle would have wanted.

“She never understood why people were mean to each other. That always kind of broke her heart,” her mother said