The teenage stepbrother of Anna Kepner “is a suspect” in the 18-year-old’s death on a cruise ship, according to new court documents filed by both of the stepbrother’s parents as part of a child custody case. Anna Kepner died on the Carnival Horizon on Nov. 7 while the cruise ship was at sea, according to the Miami-Dade County medical examiner. The 18-year-old’s body was found by a housekeeper under the bed in her stateroom the day before the ship docked in Miami, law enforcement sources told CBS