*Updated* Tuesday A.M. - Jennifer Hudson's nephew

Academy Award-winning singer and actress Jennifer Hudson stood again in the Cook County medical examiner's office, clutching the hands of loved ones as they identified the body of yet another slain relative -- her 7-year-old nephew, Julian King.
Even before family members arrived at the morgue Monday, they had been told that the three-day search for the 2nd grader had ended when his body was found slumped in the back seat of a sport-utility vehicle parked on a West Side street.
Amid visibly shaken family members in the medical examiner's office, Hudson bowed her head as if in prayer, then looked up.
"Yes, that's him," she told medical examiner officials as the family stood with her in an adjoining room and looked at a video monitor showing the boy's face.
The toll was inescapable: Hudson had lost her mother, her brother and now her nephew to a murderous rampage.
Even as the family gathered to answer one painful question, police searched the Chevrolet Suburban to answer others.
Officers questioned William Balfour, 27, the estranged husband of Julian's mother, on Friday night, but he stopped talking when police suggested he take a polygraph test, law-enforcement sources said. Balfour has not been charged in the slayings.
Although the sources say Balfour remains the focus of the investigation, the motive remains murky. Police say there have been ongoing disputes between him and his estranged wife, Julia Hudson, and her family.
Hudson's mother and brother had thrown him out of their Englewood house in the past, sources said. Julia Hudson also told police that Balfour had threatened the family. A source said Balfour told Julia Hudson he would kill her if he found out she had a boyfriend, despite the fact that he had other girlfriends.
In another incident, sources said, Julia Hudson arrived Friday morning at Sunrise Bus Co. on payday and discovered her wages had been garnished because of unpaid car payments. Sources said Balfour had taken her car months earlier but promised to make the payments on the vehicle. After seeing her pay stub, Julia Hudson called Balfour to complain about the unpaid bills, sources said.
Police believe that Balfour went to the Hudson family home Friday and shot through the front door, striking Hudson's brother, Jason. Hudson's mother, Darnell Donerson, came into the living room, screaming, and Balfour shot her as well, sources said. Shell casings were also found in the child's room, but there were no bullet holes or other signs of violence there. Much of the account of what police believe happened that day came from an interview with a girlfriend of Balfour's, sources said.
The sources also said Balfour's girlfriend contradicted his alibi and told police that he was involved in the slayings.
Police have not ruled out the possibility that more than one person was involved, though Supt. Jody Weis said Monday that Balfour was currently their only "person of interest."
On Sunday morning, officials transferred Balfour to Stateville Correctional Center, saying that because he was a suspect in the slayings, he violated conditions of parole for a 1999 conviction for attempted murder.
Over the weekend, the city scoured the area near the first shooting scene and a grid east of where the boy eventually was found. Officers and volunteers taped missing-person posters up in area shops, and vigils were held in Englewood.
But Julian was found Monday morning on the West Side after a tiny dog named Li'l Man howled and barked at an unfamiliar white SUV parked in the 1300 block of South Kolin Avenue.
The Chihuahua's reaction drew the attention of his owner, John Louden. The SUV matched the description of one police had sought in the killings since Friday. It remains unclear if police had canvassed the block, but some neighbors say they had seen the SUV since Friday. But no one called police before Monday.
Louden, 75, went inside and told his wife, Lynnette. Neighbors said the pace of drug dealing nearby often brought strange cars to the block. But when the Loudens saw the Suburban's license-plate number appear on television, Lynnette Louden called 911.
"The first thing I thought was," she said, " 'Lord, don't let the baby be in there.' "
But he was.
Julian was found slumped over in the back seat of the Suburban, shot in the head. A bullet was found lodged in the vehicle, leading detectives to believe he had been shot in the vehicle. Police don't know precisely when he was killed, saying they are waiting for more information from the medical examiner's office. Police are hoping to find physical evidence at the two crime scenes that breaks the case.
A prayer service was held for the three slain family members in Pleasant Gift Missionary Baptist Church, where one of Hudson's cousins is a minister.
And on the block where the shootings happened near 70th Street and Yale Avenue, about 100 friends and strangers gathered for a candlelight vigil of song and prayer Monday evening.
Surrounded by stuffed animals, balloons and posters that had grown throughout the day, the crowd sang Jennifer Hudson's song "Spotlight."
On behalf of the Hudson family, the Pleasant Gift Missionary Baptist Church announced establishment of the Hudson-King Domestic Violence Prevention Fund, c/o Seaway Bank and Trust Co., P.O. Box 19522, Chicago, Ill., 60619.
Angela Rozas, David Heinzmann and Robert Mitchum, Chicago Tribune
Tribune reporters Liam Ford, Jeff Long, Azam Ahmed, Emma Graves Fitzsimmons, Stacy St. Clair, Jeff Coen, Dan P. Blake and James Janega contributed to this report.