Anna Kepner, an 18-year-old American cheerleader, was found dead on the Carnival Horizon cruise ship and her death is being investigated as a homicide by the FBI due to asphyxiation caused by strangulation.The investigative focus is on her 16-year-old stepbrother, who has been named a suspect and released pending further inquiry, while her stepmother Shauntel Hudson requested a custody hearing postponement amid the ongoing probe.