The death of 18-year-old Anna Kepner aboard a Carnival cruise ship has officially been ruled a homicide. According to reporting by ABC News, the Florida teen’s family provided the network with a copy of her death certificate, which lists the cause as “mechanical asphyxia.” The document goes further, saying Kepner was “mechanically asphyxiated by other person(s).” The date of her fatal injury is recorded as Nov. 6.

Kepner’s body was discovered under a bed by a housekeeper on the Carnival Horizon, where she was traveling with her father, stepmother, three stepsiblings, and grandparents. The night before she vanished, she told family members she wasn’t feeling well and returned to her room to rest. By morning, she was missing. Soon after, she was found dead.
Because the ship was in international waters, the FBI took the lead on the investigation. Agents have been interviewing family members, crew, and passengers as they try to piece together what happened during the final hours of Kepner’s life.

A recent court filing has added a jarring layer to the case. Kepner’s stepmother, Shauntel Hudson, disclosed in a custody dispute with her ex-husband that one of the teen’s stepsiblings could face charges tied to her death. Hudson’s filing responded to an emergency motion filed by her ex, Thomas Hudson, who claimed their “sixteen year old child is now a suspect in the death of the step child during the cruise.”

Family members have described Kepner and her stepbrother as unusually close. Her grandparents told ABC News the pair were like “two peas in a pod,” inseparable throughout the trip. Barbara Kepner, Anna’s grandmother, said the boy was visibly distraught when her body was found.

The FBI has not confirmed whether the teen’s stepbrother is a suspect, only that the investigation remains active and ongoing. For now, the death certificate casts a grim shadow over a family vacation that turned into a crime scene at sea, with more questions than answers and a homicide ruling that leaves little room for doubt about what investigators believe happened in that cabin.