Chengxu Wang, then five, was last seen in Champaign, Illinois, on February 7, 2015, when he and his twin sister Zhaoxu vanished. Chengxu was described as 3 feet 4 inches tall, about 50 pounds, with black hair and brown eyes. The disappearance has been treated as a family abduction; investigators have focused on the twins’ non-custodial mother as the person believed to have taken them.

Details and photographs of the mother have not been made widely available, complicating public tips. The Champaign Police Department has continued the investigation, but no confirmed whereabouts for Chengxu or his sister have been reported and the trail has grown cold.

If anyone has information about Chengxu, Zhaoxu, or the mother who may have taken them, please share what is known with investigators.