. >> hi, i'm caedon. >> what's your name?d julian. they all seem to be paying close attention during the behavior skills gun safety class. harrison and julian's mom says her boys have very different personalities. >> jillian is sort of the funny kid. he's always laughing. he's very curious. at times, he will test -- test the limits whereas harrison's more of a rule follower. >> reporter: our other set of siblings also have very different personalities. their dad thinks caedon will stay away from the gun, but nolan being the curious type -- >> i think he'll be the one to go ahead and maybe grab a gun. >> reporter: caedon and nolan's parents keep a gun in their house. it's locked and the boys don't know where it is. >> so you want to get started on the letters? >> reporter: as their kids begin the test, the parents get anxious. and we wonder will this new training make a difference. >> it's a nail biter. >> but your heart is racing right now -- >> a little -- a little shaky. yeah, and my hands are a little shaky. >> coming up -