Caitlin Lee, 15, killed herself in October 2011, when she ran away from the group home where she lived in Naperville, following a number of suicide threats. Her family believes the state should not have put her in a group home, but kept her at a different facility where she was doing well. (Family Photo)

NAPERVILLE, Ill. (CBS) — A teenage girl who took her life on railroad tracks in Naperville last month was a resident of a home that is supposed to protect some of the state’s most vulnerable young people.

CBS 2’s Dave Savini investigated allegations the home was out of control.

ChildServ in Naperville is where 15-year-old Caitlin Lee lived until she took her own life on nearby railroad tracks.

Her mother, Mary Lee, blames the system and the home that was supposed to take care of her troubled daughter, who was a danger to herself and became a ward of the state.

“I just remember screaming out, ‘I told you this was going to happen,'” Mary Lee said about her daughter, who reportedly was not doing well at ChildServ.

During her three-month stay at ChildServ, Lee ran away 17 times. In fact, in the nine days leading up to her death, she ran away six times.

Caitlin’s grandfather, Patrick Ward – a former elected state’s attorney in Lee County – says Caitlin was doing better at a different facility and she should not have been moved to ChildServ.

“She was my girl. She shouldn’t have been released from the only place she was safe,” said Ward. “And we tried and we yelled and we screamed and we begged.”

CBS 2’s investigation uncovered police records showing Naperville police were called to the home 625 times in just two years.

Naperville Police Chief David Dial says the 911 calls doubled in the last two years. The calls included fights, suicide threats, even one for sexual assault; but the vast majority were for runaways like Caitlin.

“I cannot explain why this is permitted to go on by DCFS,” said Dial. “She should have never been in a setting like a group home.”

On the night of her suicide, Lee even made threats to hurt herself after an earlier altercation with another girl in the home. Police say they did not get a call about the earlier altercation, but instead were called after the suicide threats and after she ran away.

“I think we should have been called,” Dial said.

ChildServ also has homes in Downers Grove and Lisle. Police were called to those homes, combined, more than 500 times in the past two years.

The head of ChildServ chose not to comment.

A DCFS official said the performance of these three group homes is not acceptable and the homes are under a quality improvement plan to address problems including how to better handle runaway behavior.