Grandparents of boy claim neglect resulting in his death.
Ian Sousis was supposed to be supervised at all times.
Kentucky officials say investigation is continuing.
The family of a 9-year-old boy who walked away from Children's Home of Northern Kentucky in June and was found drowned in the Ohio River says in a federal lawsuit that the agency negligently caused his death.
James and Rhonda O'Brien of Highland, Kentucky, filed the lawsuit on Nov. 23 in federal court in Lexington. In addition to the children's home and some of its employees, the lawsuit names the commonwealth of Kentucky and the Cabinet for Health and Family Services.
On June 4, sometime after 9 a.m., Ian Sousis fled the children's home in Covington. A 911 call about the missing boy, who was small at about 4-foot-2 and 65 pounds, came to Kenton County dispatchers at 9:32 a.m.
"He was heading down − they call them the AWOL steps,” a woman who identified herself as Christina told the 911 dispatcher. (AWOL is a military term meaning absent without leave.) The steps with that nickname are near where Ian had been living. They run through a wooded area and into the city. An employee pursued Ian 13 seconds after he left, police later said, but the boy got away.