Antonio Whitlow, 33, was arrested Saturday in Memphis, Tenn., hours after his parents were found slain in their home in Little Rock, about 135 miles away.
His sister was with him and seemed unharmed, Little Rock Police Sgt. Cassandra Davis said Sunday.
"Amber has not been harmed physically, physically, she is fine," said Sgt. Cassandra Davis with the Little Rock Police Department. "Mentally, she's as well as a 12-year-old would be."
Grady Carter made the 911 call Saturday afternoon when he arrived at the Whitlow's to discuss Sunday morning's sermon. That's when he found the pastor and his wife lying dead on the floor.
"That's something that I don't really want to keep on my mind," he said. "The Lord's going to help me take care of that."
"She was the type of young lady that always wanted to do something for somebody," said victim Annette Whitlow's sister, Rose Harshaw. "She always wanted to be a help to someone."
Amber Whitlow will remain in with the Department of Human Services until the victim's family members can make arrangements for her custody.
Davis declined to say whether investigators believe the child witnessed her 65-year-old parents, Bobby and Annette Whitlow, get killed. She said she didn't know whether the girl and her brother, who was much older, ever lived with their parents at the same time.
Investigators, in a police report, listed a knife or some other sharp object as the weapon used to kill the couple. Davis said detectives hadn't determined a motive for the slayings.
Police said the couple was killed between noon and 3 p.m. Saturday, when officers were called to the home by a church member who had gone to the victims' home to meet Bobby Whitlow and saw Annette Whitlow lying on the living room floor by a fireplace. Officers found Bobby Whitlow dead in the kitchen.
An Amber Alert was issued for the girl and police in Memphis found Whitlow and his sister walking along Beale Street, in the city's tourism district, at about 10 p.m. Saturday, according to Memphis Police Sgt. Alyssa Macon-Moore.
In the 2007 case, Whitlow initially pleaded not guilty by reason of mental disease or deficiency to aggravated assault of a family or household member. Pulaski County Circuit Court's online records don't specify the nature of Whitlow's alleged mental illness or deficiency, or the nature of the assault. They do name his female victim, and it wasn't his mother or the sister he's accused of abducting. The woman's relationship to Whitlow wasn't immediately clear.
After a psychiatric evaluation deemed Whitlow fit to stand trial, he changed his plea to guilty and was sentenced to five years' probation, which would have expired in October.
Whitlow's attorney in that case, Patrick Benca, said Sunday that he hasn't had contact with Whitlow, and described him as not "an unlikeable guy."
"It would surprise me, I'll just say that," if Whitlow killed his parents, said Benca. He said he didn't remember the nature of Whitlow's alleged psychiatric problem, and that he wouldn't discuss it even if he did.
Whitlow remained in custody in Memphis, pending extradition, Davis said.
"We'll have to first start the (extradition) process on Monday," she said.
The process could take two or three days if Whitlow does not fight extradition, weeks if he does fight, Davis said.
"It just depends on the legal system," she said.