GWINNETT COUNTY, Ga. — Channel 2′s Tony Thomas has uncovered disturbing details about the conditions a Gwinnett County family lived in before a fire ripped through their home.

Investigators said a 15-year-old started the fire that killed his 10-year-old sister.

Gwinnett police have now launched a child abuse investigation so, Channel 2 has decided not to identify the teenage suspect.

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The 15-year-old is being held in a regional youth detention facility as his parents face a fight to keep their three remaining children.

State investigators said the children lived in deplorable conditions for years, and they believe that treatment will likely recur if they are allowed to remain at home.

Neighbors were shocked to learn what was allegedly happening behind the tall white fence on Beaver Road in South Gwinnett.

“That’s, I don’t know what to say, sick people in the world,” neighbor Mike Kilgore said.

A state investigator wrote an affidavit to take the three remaining children — ages 17, 12 and 8 — into state custody, saying, “The children have not been in school in years, the home has no sewage system, the children have been using buckets to relieve themselves, and none of the children have had a shower in possibly months. It is unclear how the children are impacted, as they have not been outside the home in years.”

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Gwinnett police said Sunday the family was cooperating in the fire investigation. Hours later, a murder warrant was issued for the 15-year-old, saying he caused the death of his 10-year-old sister “by setting the residence on fire when the defendant knew his family was inside.”

The files paint a very disturbing picture of life in the house, but from NewsDrone2, Thomas could see play items in the yard: a trampoline, a green slide and a playhouse.

“We believe this is an isolated incident. We don’t believe there is a threat to the community or any of the neighbors,” investigator Christian D’allaird said.

Thomas is waiting for word from the Georgia Department of Human Services, which oversees DFACS, on whether the agency had any contact with the family prior to the fire.

“They pretty well stayed secluded,” Kilgore said.

Attempts to reach the parents today were unsuccessful.

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