Friends bring bundles of balloons and flowers to place on the car of Anna Kepner, an 18-year-old Temple Christian School student who died aboard the Carnival Horizon cruise ship.

Authorities are looking into the stepbrother of an 18-year-old who was killed aboard a Carnival Cruise Line ship earlier this month, per court documents and family statements.

The victim, Anna Kepner, was traveling on the Carnival Horizon voyage when she died.

Online records from the Miami Dade Medical Examiner Department show that Kepner died around 11:17 a.m. on Nov. 7. When contacted on Nov. 21, the department said her cause and manner of death haven’t been determined, and her report is pending.

Her family told ABC News that she died from asphyxiation. USA TODAY has attempted to contact Kepner's family members but has not received a response.

According to court documents obtained by USA TODAY, Kepner’s stepmother Shauntel Hudson was previously married and shares a 16-year-old son with her ex-husband; the pair have an open custody case. In court documents filed on Nov. 17, Hudson’s lawyers identified a 16-year-old as a suspect in connection to Kepner’s death.

The Federal Bureau of Investigation (FBI) is investigating Kepner's death, according to a statement Carnival Cruise Line provided to USA TODAY. The Cruise line said it is fully cooperating with the FBI's investigation.

The FBI told USA TODAY on Nov. 21 that the FBI does not provide operational updates on its investigations “except in rare circumstances.”

"The sixteen year old child is now a suspect in the death of the step child during the cruise," wrote Hudson’s lawyers, adding in another document that the children involved in the custody case were on the cruise with their mother and Kepner.

The 16-year-old teenager identified as a suspect is staying with a family member of his mother in the Hernando County area, according to Florida Today, part of the USA TODAY network.

When contacted by email on Nov. 21, a lawyer representing Hudson did not immediately respond.

As the case remains under investigation, here's what we know so far.

What happened on the cruise ship that day?

Kepner, 18, is from Titusville, about 50 miles east of Orlando. She was found dead aboard the Carnival Horizon cruise ship Nov. 7. She was on the ship with her father, stepmother, her grandparents, and stepsiblings, per Florida Today.

A crew member cleaning the cabin Kepner was staying in found her body under a bed on Nov. 7, Florida Today reported.

Her paternal grandmother, Barbara Kepner, told ABC News that the family's two younger girls stayed with their parents, while Anna and two other teens had a room together, including the stepbrother, now identified as a suspect in connection to her death.

"We had a larger room and we made it very clear that at any time if they weren't getting along, they didn't want to be together, we had an extra bed in our room that they could come to,” her grandmother told ABC News.

Based on security footage, the stepbrother was the only one seen entering and exiting the room Anna shared with him, the girl's grandmother told ABC News.

Earlier that day, Kepner's braces were bothering her and she wasn't feeling well, so she went back to her room for a bit, her grandmother told ABC News. She eventually came back down and spent time with family in the casino.

"She said, ‘Meemaw, I love you guys. I'll see you later,’" her grandmother recalled. "She'd pop in and out to check in with us. And we never saw her again after that.”

The next morning, her grandfather, Jeffrey Kepner, said he was buying bingo cards when he heard a medical alert over the ship's intercom. He heard his granddaughter's room number. According to ABC News, there were bruises on the girl's neck.

Grandmother says Anna Kepner and stepbrother were close, per ABC News report

Kepner's grandmother told ABC News the teenager and her stepbrother were "just like brother and sister" and "two peas in a pod."

“I know that those two kids cared about each other in the right way,” the grandmother told ABC News. “I can't accuse him because I don't know what happened in that room."

The girl's grandmother said her stepbrother "does not remember what happened,” and she believes him.

“He was an emotional mess," Kepner's grandmother said. "He couldn't even speak. He couldn't believe what had happened."

Once the boat docked in Miami, the boy was hospitalized for psychiatric observation and then released to family members.

Family remembers ‘Anna Banana’ as a sweet, funny teenager

Kepner was laid to rest on Thursday, Nov. 20 at The Grove Church in Titusville. Lovingly calling her “Anna Banana” and “sunshine,” Kepner’s family said in her obituary that she was bubbly, funny, and had no filter.

She loved doing her makeup, making TikTok videos, and spending time with her grandparents. She spent lots of time with her siblings, taking them to the park, or out for Halloween Horror Nights, her family wrote.

She was known to send sweet messages, reminding those around her that she loved them.

She also loved music, her family said, adding that she liked all genres except heavy metal, and was a huge fan of Shawn Mendes.

She was set to graduate from Temple Christian School in 2026. She planned to join the U.S. Navy after graduation with hopes of becoming a K-9 police officer. She was also passionate about sports and was a Georgia Bulldogs fan, her family said. She’d often dream of becoming a cheerleader for the Bulldogs.

“The Kepner family asks for privacy and respect during this difficult time,” they wrote in her obituary. “And for everyone to remember Anna with laughter, color, sunshine, and love. Because that’s exactly how she lived her life … She danced in the light she left behind and it will never fade.”

Saleen Martin is a reporter on USA TODAY's NOW team. She is from Norfolk, Virginia – the 757. Email her at sdmartin@usatoday.com.

This article originally appeared on USA TODAY: What happened to Anna Kepner? Stepbrother named suspect in cruise ship death.

Reporting by Saleen Martin and Michelle Spitzer, USA TODAY / USA TODAY

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