Documents show that a suspect in the Chicago murders of three members of Jennifer Hudson's family was arrested for drug possession in June, but state officials didn't revoke his parole.

Parole records obtained by The Associated Press also indicate that William Balfour missed a meeting with his parole agent on Friday. That's the day Hudson's mother and brother were murdered and her 7-year-old nephew vanished.

Balfour is the estranged husband of Oscar-winner Hudson's sister. He is being held on an unrelated parole violation and police have named him a person of interest. No one has been charged with the killings.

Hudson's nephew was found dead Monday. Authorities said Tuesday that he died of multiple gunshot wounds.

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Hudson was among seven family members and close friends who cried and held hands as they identified 7-year-old Julian King's body from a live image on a television screen at the Cook County Medical Examiner's office Monday afternoon.

With two crime scenes, a suspect in custody and an outraged community, Chicago's top cop said he is confident investigators will find clues to solve the deaths of Hudson's mother, brother and nephew.

"I suspect we'll have some evidence that will link us to the killer," said Police Superintendent Jody Weis, adding that surveillance cameras throughout the city may have captured images that would help the investigation.

Weis said a motive remained unclear. Police have characterized the slayings as "domestic related" and authorities have been questioning Balfour. No one has been charged in the slayings.

"It wasn't a case of a stranger-type homicide," Weis said.

Julian's body was found early Monday in the rear seat of the SUV, which was parked on the street in a neighborhood of brownstone homes and apartment buildings about 10 miles from his home. The SUV had been the subject of an Amber Alert issued Friday after Hudson's mother and brother were found slain.

Lynette Louden, 47, said she called police about the SUV across the street from her home on Chicago's West Side after her family's Chihuahua started barking at it early Monday. Some neighbors said they hadn't seen the vehicle before Monday, but Louden said it had been there since at least Saturday.

"I only hoped the body wasn't in there," she said. "When they said that it was, I cried."

When asked how officers could have missed the SUV during their massive search, Weis noted that Chicago is a big city and that the vehicle was "several miles away from the first crime scene."

Corrections records show that Balfour spent nearly seven years in prison for attempted murder, vehicular hijacking and possessing a stolen vehicle. He was expected to remain in state custody until the Illinois Prisoner Review Board looked at his case.

Balfour's mother, Michele Balfour, has said Hudson's mother kicked Balfour out of the family home last winter. She denied her son had anything to do with the killings.

It was unclear whether Balfour had an attorney.

Steve Peterson, head of the department's Bureau of Investigative Services, said the search for the boy had been centered farther east based on information they had about where Balfour's current girlfriend lives.

Hudson, 27, who started out on "American Idol" and won an Academy Award for best supporting actress in 2007 for her role in "Dreamgirls," returned to Chicago to be with her family during the weekend. She also had identified the bodies of her mother and brother.

At a candlelight vigil Monday night, hundreds of people gathered outside the Englewood home where the two bodies were found. They sang, held hands and cried in the cold as they contributed to an expanding memorial of stuffed animals, balloons and flowers.

Many said they could not understand how someone could shoot a little boy.

"It pains all of us to know three lives are gone and we don't know why," said Doris Jones, who lives in the neighborhood.