TITUSVILLE, FLORIDA — A federal grand jury in the Southern District of Florida indicted the 16-year-old stepbrother of Anna Kepner on first-degree murder and aggravated sexual abuse charges for her killing aboard the Carnival Horizon cruise ship. The U.S. Department of Justice alleges the teenager sexually assaulted and intentionally killed the 18-year-old while the vessel was in international waters during a Caribbean voyage in November 2025.

The stepbrother was initially charged as a juvenile in February, and the case remained sealed until U.S. District Judge Beth Bloom ordered it transferred for adult prosecution. If convicted, he faces a maximum penalty of life in prison.

U.S. Attorney for the Southern District of Florida Jason A. Reding Quiñones said in a news release: "Our hearts go out to the victim's family during this unimaginable loss. A federal grand jury has returned an indictment charging serious offenses that allegedly occurred aboard a vessel in international waters. We will present the evidence in court and pursue this case with professionalism and care."

According to court records, the stepbrother was traveling on the Carnival Horizon with Kepner and other family members, including her father, stepmother, and grandparents. Kepner's body was found under a bed, wrapped in a blanket and covered by life vests. The Miami-Dade medical examiner's office determined that she died of mechanical asphyxia.

Kepner was a cheerleader who had been expected to graduate from a secondary school in Florida in May and had wanted to join the military. Former Palm Beach prosecutor Dave Aronberg said the transfer to adult court was expected.

"It was inevitable that the stepbrother would be charged as an adult," Aronberg said. "The adult criminal justice system is better equipped to handle a 16-year accused of such violent crimes that result in death."

FBI Miami is investigating the case. Assistant U.S. Attorney Alejandra L. López is prosecuting. The stepbrother is presumed innocent unless and until proven guilty.