Eaton said that court records indicated that the remains of seven-year-old Joshua “JJ” Vallow, and 17-year-old Tylee Ryan showed signs of "torture."
"We know that JJ was wrapped in plastic. He was wrapped in duct tape," Eaton said. "There was a white plastic bag over his head.
"I don't think these kids were simply put to sleep and then buried."
"Tylee's remains were burned. She was dismembered. She was buried in the ground," Eaton asserted. "It's not like these bodies were simply buried in a decent manner. They were tortured, in a way."
Eaton also claimed that the court documents indicate that Tylee was dismembered, though he noted that it is unclear whether that occurred before or after she died.
"We don't know the specifics about that," he added. "But we do know that her remains were also burned and they found bones when they discovered her body."
The children's remains were found on June 9 on the Idaho property of Chad Daybell, 51, a self-published author of doomsday novels who has been charged with disposing of the youths' bodies on separate dates in September — the same month the children were reported missing by relatives.
Vallow, 46, has been jailed on child abandonment charges. The couple is being held on a $1 million bond each.
"Where's the murder charge?" host Nancy Grace asked. "What's the holdup? ... Why just concealment?"
Eaton told Grace that Vallow and Daybell could be facing the death penalty "considering all of the factors and considering the manner in which they were disposed."
Fox News' Michael Ruiz and Matt London contributed to this report.