HOUSTON (KTRK) -- Harris County deputies made three trips to the home where two adults and 6 children were murdered before realizing anything was wrong.
According to law enforcement sources, Valerie Jackson's mother called the Harris County Sheriff's Office from Minnesota at 10:44 am Saturday after getting a message from her saying David Conley, her ex-boyfriend- had a gun. When deputies responded, no one answered the door.
At 4:36pm and 5:41pm, there were two more trips. By 7:55pm, after a plea from a sister in Chicago, deputies returned only to see the lifeless body of a child inside.
Relatives question whether these were missed opportunities to prevent the tragedy. Investigators have not revealed how long the victims may have been dead.
"He's the devil, the devil! An evil person would kill a six year old and the mother of your children," said Vernessa Conley, Conley's estranged wife. The two married in 1986, she said. She left him after less than a year, but the two never divorced.
"He used to just grab me, pull my hair, slap me around, push me," Conley added.
She said about a month ago, she tried to talk Jackson into getting away from Conley. Instead Jackson and her husband, Dwayne Jackson, their five children and Conley's own 13-year-old son were shot to death sometime Saturday. Sources tell Eyewitness News Conley bought a gun online two weeks ago.
Eyewitness News has also learned the family was investigated several times by Child Protective Services. Yet, court records show that the case filed by CPS was dismissed in the courtroom of Judge Glenn Devlin in 2014.
PHOTOS: Scene where 6 children and 2 adults were found dead
Monday morning, David Conley said nothing in his first court appearance.
Prosecutors revealed Valerie Jackson texted her own mother out of state to let her know Conley had gotten into the home.
"My heart goes out to the mother who received the text from her daughter that she was in trouble, and the mother was many states away but, of course, did what any mother would do and called 911," District Attorney Devon Anderson said.
It is unclear exactly when that message was received. What we do know is that Saturday night, Harris County Sheriff's deputies responded to the scene, and a standoff ensued with Conley. Those tense moments were captured on surveillance video, which was obtained exclusively by Eyewitness News.
The video shows sheriff's deputies with their guns out, taking precautions during the standup. At one point, a deputy is seen trying to turn off a flood light in a neighboring house. Eventually, Conley surrendered. By then, all eight family members were dead.
In hindsight, neighbors say it never should have come to this.
Court documents obtained by Eyewitness News show Child Protective Services first had contact with the family in 2011. Documented interviews with the oldest child, Nate Conley, showed he was often "whooped" for no reason. His friends remember how scared the teen was.
"He was right there almost crying, and really sad, and I was like 'Why are you here?' He was like, I'm scared to go home, don't want to go home,'" recalled Carlos Sanchez, a teenage neighbor.
Court documents also show that the children were often left home alone, and numerous complaints of abuse came into CPS offices. However, documents show in 2014, the CPS case was dismissed in Judge Glenn Devlin's court. Court documents do not specify the reason. Neighbors say they remember a time when the children were away from the home, but confirm they moved back in a few months ago.
"You would see the kids, outside, they would always be outside, and not comfortable being inside," said Wendy Antonio, another neighbor.
During Monday's hearing, there was no mention of a lawyer either appointed or hired. His only response was to acknowledge his name when asked by the judge, who also read him his rights.
Those killed, who all were shot in the head, were identified as parents Dwayne Jackson, 50; his wife, Valerie Jackson, 40; and their children Dwayne, 10; Honesty, 11; Caleb, 9; Trinity, 7; and Jonah, 6. Also killed was a 13-year-old, Nathaniel, who was believed to be Conley's son from the relationship with Valerie Jackson.
Most of the victims had been handcuffed and some had been shot multiple times, police have said.
"We do not - cannot - fully comprehend the motivation of an individual that would take the lives of so many innocent people. Especially the lives of the young ones," said Chief Deputy Tim Cannon of the Harris County Sheriff's Office. "The killer's motives appear to be related to a dispute with Valerie, who was his former domestic partner."
Anderson said it would be three to four months before she decides whether to seek the death penalty.
The request from Valerie Jackson's mother Saturday sent deputies to the home in northwest Houston.
"Upon arrival, deputies made multiple attempts to establish contact with residents inside the home. No contact was made," Cannon said.
After authorities learned that Conley, who had once lived in the home, had a warrant for his arrest for an assault charge, the sheriff's office High Risk Operations Unit was called.
"While awaiting response for the (unit), the body of an unidentified child was observed through a window at the residence," he said. "Deputies on scene forced entry into the home and were immediately met with gunfire. The deputies withdrew from the home ... and awaited the arrival of the unit."
A standoff ensued for several hours until Conley surrendered, said Sgt. Craig Clopton, the lead investigator.
Investigators declined to say when on Saturday the victims were shot or if any victims were alive when deputies first tried to enter the home.
According to an arrest affidavit, Conley told authorities that he discovered on Saturday morning that the locks had been changed at the home after he had moved out. He entered the home through an unlocked window, the affidavit said.
According to Clopton, Jackson and Conley had a relationship, which ended, and "then (Dwayne Jackson) began a relationship with Valerie, which led to five children."
That relationship ended and Conley and Valerie Jackson began another relationship, before breaking up again, Clopton said.
Court records show Conley's criminal history dates back to at least 1988, with the most recent incident last month, when he was charged with assault after allegedly assaulting Valerie Jackson at the home where the bodies were found. Conley pushed Valerie Jackson's head against a refrigerator multiple times after she tried to stop him from disciplining her son with a belt, the documents alleged. The case was still pending.
In 2013, Conley was charged with aggravated assault for threatening Jackson with a knife. He pleaded guilty and was sentenced to nine months in the county jail.
In 2000, he was sentenced to five years in prison for retaliating against his then-girlfriend after she had filed an assault charge against him. It was unclear if that woman was Valerie Jackson.
Authorities declined to comment on assault charges Conley had faced in the past.
The Associated Press contributed to this report.