Smithfield, N.C. — A former Smithfield paramedic on Tuesday said it was  eerily quiet when he arrived at a Johnston County farmhouse where a 4-year-old boy died two years ago.

Lynn Paddock, 47, is charged with murder in the Feb. 26, 2006, death of her adopted son, Sean. Investigators said Sean suffocated after she wrapped him tightly in a blanket to keep him from wandering around the house at night.

Defense attorneys insist the death was accidental, not punishment or discipline.

Paramedic Chris Credle testified Tuesday afternoon that Sean was "stiff as a board" when he arrived at the Paddock house in response to a 911 call. That indicated the child had been dead for some time, he said.

"I knew I couldn't do anything for him," Credle said, choking up when he was asked to identify a picture of Sean.

The atmosphere inside the Paddock house was odd, he said.

"In the other room, we could hear whispers," he said. "Usually, there's a whole lot of commotion going on, but there was (none) that morning."

When asked about Lynn Paddock, Credle testified that she passed briefly through the room while he worked on Sean. Later, she sat with her arms crossed or hands clenched at the hospital, he said.

"It was almost like they were getting tighter and tighter so you could see the whites of her knuckles," he said. "She was very straight (and) angry – just mad."

Credle's testimony came after a week of pre-trial maneuvering by prosecutors and defense attorneys in Paddock's murder trial.

Earlier Tuesday, Superior Court Judge Knox Jenkins ruled that three other adopted children couldn't be shielded from Paddock when they testify against her.

Prosecutors were seeking to allow David Vorenkamp, Hannah Paddock and Kayla Paddock testify from a separate Johnston County Courthouse room that would be connected by closed-circuit television to the courtroom where Lynn Paddock is on trial.

Jenkins said he didn't want to risk any video testimony being overturned on appeal, forcing the children to have to testify at a second trial. Instead, he agreed to allow a guardian to stand in the witness box with the children as they testify.

Lynn and Johnny Paddock adopted six children from the mid-1990s to 2005, when Sean, David and Hannah – biological siblings – were placed with the family.

Two older adopted children and Johnny Paddock's daughter from a previous marriage testified last week that Lynn Paddock habitually abused all of the children for years. She beat them, had them run in place or jump on a trampoline for hours, forced them to sit in their urine and at least twice shoved feces in the mouths of younger children, they testified.

Dr. Sharon Cooper, a forensic pediatrician who has evaluated all of the Paddock children in recent months, said Tuesday that facing Lynn Paddock in court would be frightening for the younger children. All five of the surviving adopted children suffer post-traumatic stress, she said.

Hannah Paddock, for example, has devised a "safety plan" for dealing with he emotions if she were to see Lynn Paddock again, Cooper said. David Vorenkamp, who has since been adopted by another family, has a habit of wringing his hands and crying, she said, while Kayla Paddock bites and stabs at herself.

Prosecutors also noted that Tami Paddock, one of the older children who testified last week, suffered a breakdown after her testimony. It was unclear how severe the episode was.

Down the hall from the trial, an adoption agency asked for a civil lawsuit filed by Sean Paddock's biological family to be moved to Wake County. The boy's grandfather filed a wrongful death suit against the agency, the state and Wake County Social Services offices in February.

There was no ruling Tuesday on the request.