Where are Joshua "JJ" Vallow, 7, and his sister, Tylee Ryan, 17? That's the question investigators, including police in Rexburg, Idaho and the FBI want answered. The kids haven't been seen since Sept. 23. Police say the children's mother, Lori Vallow Daybell, and her new husband, Chad Daybell, haven't been cooperative in helping find them. Chad and Lori married just weeks after Chad's wife's death, which is now also under investigation. Chad and Lori Daybell have denied any wrongdoing.