Search for missing Hudson nephew

Police investigating the killing of actress Jennifer Hudson's mother and brother are still trying to find the missing seven-year-old

The mother and brother of American actress Jennifer Hudson were found dead on Friday at this house in Chicago.

Darnell Donerson and Jason Hudson had been shot.

Hudson's seven-year-old nephew Julian King hasn't been seen since.

Police have asked the FBI to help trace him.

Hudson's sister is appealing for his safe return.

SOUNDBITE: Julia Hudson saying (English):

"I just often feel he's out there. I know he's out there. Just let him go. Put him on the side of the street. He'll sit there. Just let him go, somebody will see him."

Police are questioning a man but have so far refused to name him or describe him as a suspect.

SOUNDBITE: Jody Weis, Chicago police superintendent, saying (English):

"We're not going to comment on that. We're just not going to tip our hand on that. We're still looking. We've got a lot of forensic information to to through. We've got a double homicide inside a home that creates a lot of potential evidence."

Hudson hit the spotlight three years ago at a contestant on the U.S. talent show American Idol.

She didn't win but she kept touring in live shows and gained Hollywood stardom when she scooped a movie role which earned her an Oscar for best supporting actress.

Paul Chapman, Reuters