They inspected urine-soaked blankets and a blood-stained sheet that were in the attic bedroom where Sean had slept the night he died.

John Butts, the state's chief medical examiner, told jurors how the blankets would have pressed so hard on Sean's lungs that he couldn't get enough air to keep his brain functioning. It would have taken several minutes, at the least, for Sean to have died, Butts said.

The evidence came during the first-degree murder trial of Lynn Paddock, a Smithfield mother accused of killing her youngest adopted son.

Ron Mazur, crime scene investigator for the Johnston County Sheriff's Department, showed jurors two pieces of plastic plumbing supply line collected from the Paddocks' home. Johnny Paddock, Lynn's husband, had handed them over, saying that his wife used them sometimes to discipline their children, Mazur testified.

Sean was the youngest of six foster children that a private agency, the Children's Home Society, helped the Paddocks adopt from 1996 to 2005.

The children have testified during the trial that their mother would strike them with the pipe to discipline them. The youngest children told social workers it was a "whipping stick."

Earlier Wednesday, a day-care teacher suggested to jurors that such discipline came even before Sean was adopted by the Paddocks. Latesha Sherrod, a day-care teacher from Wake County, said she saw bruises in January 2005 after Sean, then 3, returned from a weekend visit with the Paddocks. He hesitated to sit down, and she asked him what was wrong.

"He said his new mom hit him with a long thing," Sherrod said.

Sherrod testified that she called her supervisor at the day care, and they alerted Wake County Human Services.

Wake authorities who received the report asked Dee Ethridge, a social worker for the Johnston County Department of Social Services, to check on the Paddock children at their Smithfield farmhouse.

Ethridge testified Wednesday that she asked the older Paddock children whether they'd ever been physically disciplined. Lynn and Johnny Paddock sat with the children while Ethridge questioned them.

All the children swore they were disciplined mainly with "timeout" periods. Ethridge said the house was neat and clean, there was plenty of food in the cupboards, and the children were dressed appropriately.

Social workers in Wake County eventually concluded that Lynn Paddock was telling the truth when she said Sean had fallen out of a bunk bed at their home, causing the bruises during the visit. Wake officials closed their investigation, and two months later Sean and his older brother and sister went to live with the Paddocks permanently.