The families of two elementary school students with disabilities, who were handcuffed in school by a resource officer, have filed a lawsuit against the local sheriff's department in Kentucky.An 8-year-old boy and a 9-year-old girl, who have both been diagnosed with attention deficit hyperactivity disorder, were handcuffed around their biceps last year by Kenton County Deputy Sheriff Kevin Sumner at elementary schools in the Covington Independent Public School District, according to the lawsuit, which was filed on Monday.A video of one of the incidents, recorded by a school staff member and released by the ACLU, shows the young boy struggling and crying while sitting in a chair in handcuffs.