What was supposed to be a celebratory family cruise to the Caribbean has spiraled into one of the strangest and most haunting murder cases in recent memory.

Nearly four months after 16-year-old Anna Kepner was found dead aboard the Carnival Horizon, court filings now confirm what many feared: her 16-year-old stepbrother has been charged with her homicide.

Federal authorities have not publicly announced charges or named a suspect, and the case remains under seal. But documents obtained by CBS News reveal that on February 3, 2026, the boy — identified in court papers only as “TH” because he is a minor — was charged by the U.S. Attorney in the Southern District of Florida in connection with Anna’s death.

The charge surfaced not through a press conference, but through an emergency filing tied to an ongoing custody dispute between the teen’s father, Thomas Hudson, and his ex-wife, Shauntel Hudson, also referred to as Shauntel Kepner.

The former couple finalized their divorce in 2023 — before boarding the cruise ship that would become the scene of an international homicide investigation.

Anna’s death was ruled a homicide by asphyxiation.

On November 7, midway through the family trip, a cabin steward made a chilling discovery: Anna wrapped in a blanket, covered in life jackets, and hidden beneath a bed in the room she shared with her stepbrother.

The Carnival Horizon was sailing in international waters at the time, giving the FBI jurisdiction over the case. The ship was bound for the Caribbean when the Titusville, Florida teen was killed.

The stepbrother appeared in federal court in Miami on February 6, but media were barred from the courtroom. Because he is a minor, his identity has not been publicly released, and details of the sealed proceedings remain scarce.

“If it’s a juvenile you won’t know until he’s charged as an adult,” former Palm Beach state attorney Dave Aronberg told CBS.

Long before the charge became public through court paperwork, there were signs investigators were zeroing in on the boy.

Chris Kepner, Anna’s stepfather, previously acknowledged the uncomfortable reality that the teen may have been the only person in the cabin at the time.

“I want him to face the consequences … I will be fighting to make sure that does happen,” he told People last year. “I cannot say that he is responsible but I can’t decline. He was the only one that was in the room.”

At the same time, Anna’s mother reportedly told her ex-husband that the boy claimed to have no memory of the events surrounding Anna’s death, according to text messages later submitted in court.

In December testimony, Shauntel Kepner described the teens as inseparable.

“They wanted to stay together,” she said, according to News 6. “The three of them, like the Three Amigos, are best friends.”

Anna had chosen to share a room with her stepbrother and biological brother rather than stay with grandparents on the cruise.

Now that detail reads like a cruel twist.

Anna was a high school senior set to graduate this year. Friends say she dreamed of becoming a University of Georgia cheerleader. She had also talked about joining the military or becoming a K9 police officer.

Instead, her life ended beneath a bed in a cruise ship cabin — hidden, investigators say, in a manner that suggests deliberation.

Carnival Cruise Line has said it is cooperating fully with authorities. But beyond that, public details are thin. The sealed nature of the federal case means key questions remain unanswered: What happened inside that cabin? Was there an argument? A struggle? A motive?

And perhaps most haunting of all — how did a vacation turn into a crime scene?

As the custody dispute between the adults continues to surface fragments of information, the larger case moves forward quietly in federal court.