The Arkansas Crime Lab ruled Gracie Haddox, 43, of Nashville, Ark., died from "sharp force trauma" by being stabbed to death, according to Howard County Sheriff Bryan McJunkins.
She was stabbed "several times" by a kitchen knife by Gerald Martin, 47, who later hanged himself in a closet in the house at 310 Meadow Lane in Nashville.
McJunkins is calling the deaths murder-suicide.
Based on evidence from a cellphone at the scene, Prosecutor Bryan Chesshir said it was estimated Haddox's time of death was about 9:30 a.m. May 10.
Martin's death by hanging from a rope was briefly after 4 a.m. May 11.
Martin's purchase of a package of knives from Walmart earlier in the morning was documented with surveillance cameras at Walmart, said Chesshir.
He removed one knife from the package and the other knives were found in the back seat of a car parked at the house.
"The knife was at least 6 inches. It was found next to her body," Chesshir said. "We don't know why he bought the knives, but he did."
Martin reportedly texted Haddox's cellphone and left a message she had died about 9:40 a.m. The cellphone was found next to her body.
Martin texted his cellphone and the message was sent at 4:04 a.m.
"The texts were like handwritten notes. He (Martin) texted her phone after she was killed, and he texted his phone about himself," Chesshir said. "It was macabre."
The bodies of Haddox and Martin were discovered by Haddox's 16-year-old child after opening a bedroom door early May 12, McJunkins said. The first call about the deaths came in about 7:35 a.m. May 12.
The motive for the deaths were arguments concerning his previous girlfriends, Chesshir said.
"Some friend sent a photo of his past girlfriend, and it escalated over several days. She (Haddox) had taken the children to look at other places to live," he said.
Haddox shared the house with three of her children, one of her grandchildren and Martin.
Haddox is the mother of seven children.
One of the children, age, 17, was scheduled to graduate last Friday night from an area high school.
Martin, who is originally from Mineral Springs, Ark., had lived with Haddox for about two years.
Chesshir said this is a situation of a man on parole for murder, killing the mother of seven children.
In 1991, Martin was arrested for killing a woman in Texas. He was convicted and sentenced to life in prison in 1993 and placed on parole in 2013, Chesshir said.
"He (Martin) was on parole for life out of Texas, and the parole was transferred to Arkansas when he moved back," Chesshir said.
"There is something wrong with the system when someone is sentenced to life for murder and is let out early," he said.