US actress Jennifer Hudson and her family have offered $100,000 for the safe return of her nephew, missing since a double murder. Chicago police investigating the killing of her mother and brother have been searching the area where they lived with seven-year-old Julian. His mother Julia, the actress's sister, found the bodies at the family home. Julia's husband - the boy's stepfather - has been in custody since shortly after the killings. Darnell Donerson, 57, and Jason Hudson, 29, were both found shot dead on Friday when Julia returned from work. A statewide alert has been called in Illinois for the missing little boy. Mourners have been stopping by the Hudson home, many laying teddy bears and messages along the chain link fence around the property. "We love you," one message read. Another said: "We'll find the people who did this." News of the reward came in a statement released by Hudson's publicist, Lisa Kasteler, on Sunday evening. "Jennifer and her family appreciate the enormous amount of love, support and prayers they have received while she and her family try to cope with this tragedy and continue the search for Julian," the statement said. Julia Hudson's son, whose full name is Julian King, is believed to have been in the house with his grandmother and uncle before the shooting. Deputy Police Chief Joseph Patterson said Ms Donerson's body had been found on the living-room floor of her home in the south side of Chicago. Jason Hudson's body was discovered in the bedroom. Investigators say there did not appear to be any sign of forced entry. The authorities have issued an amber alert - the US term for a search for a missing child - for Julian King. "Detectives are working 24 hours on this case," said Chicago police spokeswoman Monique Bond. "There's a lot of forensic evidence. We have to work the evidence and try and solve this case. Most importantly, we want to find the child." The boy's stepfather, William Balfour, 27, was taken into custody for questioning after being named in a police alert regarding the child's disappearance.                                   - BBC The alert said he was considered "armed and dangerous". Mr Balfour's mother, Michele Davis Balfour, denied her son had anything to do with the killings or the boy's disappearance. She said that Ms Donerson had ordered her son to move out of the family home last winter.