SMITHFIELD, N.C. — Biological family members of a 4-year-old boy who died this past weekend say they now want custody of his two siblings, as well as answers as to why the woman charged with killing him was ever allowed to adopt the children.

Lynn Paddock, 45, was charged Sunday with second-degree murder in connection with the death of her adopted son, Sean Paddock, who was found unresponsive in his bed Sunday morning.

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She is also charged with felony child abuse. Johnston County Sheriff Steve Bizzell said she abused Sean's 8-year-old sister and 9-year-old brother, and allegedly used a PVC pipe kept in their home as a disciplinary tool.

Adoption Was Sudden, Aunt Says

Biological family members and officials said child abuse allegations were made against Paddock at least seven months before Sean and his siblings were adopted in July 2005, and that social workers investigated those allegations in January 2005.

"I want to know what research they do," said Lee Anne Ford, Sean's aunt, who now wants custody of the other two children. "How in-depth do they get with these families before they say, 'Here, let them have them?'"

Ford and her husband had temporary custody of the three children after they were taken from their biological parents' home.

Their father, Dwayne Ford, was convicted of sexually abusing Sean's sister, and family members said the children's mother was not in a position to care for them.

After about seven months, Ford said, the children became a financial strain on them. The Department of Social Services placed them in foster care.

While the Fords were trying to figure out a way to manage financially and regain custody of the children, Ford said Lynn Paddock and her husband, Johnny Paddock, suddenly adopted them.

Ford said she thinks social services should have given them more time to figure out how they would manage. She said she never knew the children were adopted and living with the Paddocks until news reports surfaced about Sean's death.

A summary of what Johnston County social workers found in their investigation last year is expected to be released Wednesday. The exact cause of Sean's death has yet to be determined.

911 Call Released

More details, however, about the events following his death were answered in a 911 call that Johnston County authorities released Tuesday.

Paddock's older daughter, Jessie, very calmly speaks to the dispatcher, explaining to him what had happened and that her younger brother was not breathing.

Meanwhile, Lynn Paddock is in the background performing CPR.

The call was received at about 7:15 a.m. Sunday. Jessie told the dispatcher that the 4-year-old was cool and stiff.

The call remains relatively calm until right before emergency workers arrive. At that point, it seems, family members realize that Sean can't be saved. Lynn Paddock becomes extremely emotional in the background.

Emergency workers pronounced the boy dead on the way to a local hospital.

The Paddocks have four other children -- Johnny Paddock's daughter from a previous marriage; a girl, now 19, whom they adopted in 1996; a boy, now 15, whom they adopted a few years later; and one other adopted child, deputies said.

Two of those children were placed in protective custody on Sunday.

Investigators are not sure how much, if anything, Johnny Paddock knew about the alleged abuse.