Chicago ? Jennifer Hudson and her family offered a $100,000 reward Sunday for the safe return of her missing nephew, as investigators looked for forensic evidence near the home where her mother and brother were found shot to death.

Mourners dressed in their Sunday best milled outside the childhood home of the singer and Oscar-winning actress, along with investigators seeking clues to the whereabouts of 7-year-old Julian King, the son of Jennifer Hudson’s sister, Julia.

Chicago police ramped up search efforts for Julian around the Englewood neighborhood, where Hudson grew up, and transferred custody of a “person of interest” in the killings to state authorities.

An Amber Alert remained in effect Sunday for Julian, who disappeared Friday, the day the bodies of his grandmother, Darnell Donerson, 57, and 29-year-old uncle Jason Hudson were found in the home they shared on the city’s South Side. The deaths were ruled homicides.