Two days after Oscar-winning actress and singer Jennifer Hudson’s mother and brother were murdered in Chicago, her 7-year-old nephew Julian King is still missing. The boy’s mother, Julia Hudson, is pleading for his safe return—and her estranged husband, William Balfour, is in police custody and being questioned. “I don’t care who you are, just let my baby go,” Julia Hudson said yesterday, standing with Julian’s father, Greg King. “I just want my son back. He doesn’t deserve this.” Balfour, who was arrested Friday, has been downgraded by police from a “suspect” to a “person of interest” in the shootings.