What started as a dream vacation soon thrust a tight-knit blended family into shock and anguish when one of their own, a beloved teenage girl, was discovered dead on a cruise ship earlier this month.

Even more baffling and heartbreaking, her grandparents said in an interview with ABC News, the person authorities told the family is suspected of Anna Kepner’s death: her stepbrother.

“We were all having a great time,” grandmother Barbara Kepner recalled of the trip. “I couldn’t fathom why anyone would wanna hurt my baby.”

The grandparents of the 18-year-old who was found dead on a cruise ship sit down with ABC News.
ABC News

Her grandparents said 18-year-old Anna Kepner had her whole life ahead of her. She was an independent and “mighty” young woman, set to graduate high school in May and aspiring to join the Navy, the Kepners said. Those hopes came to a screeching halt when Anna’s body was found aboard the Carnival Horizon, where she and eight other family members were on holiday.

A cause of death has not been announced by authorities, but the Kepner family says the FBI has told them Anna apparently died from asphyxiation, possibly caused by a bar hold — an arm across the neck.

Teen found dead on Carnival cruise died by asphyxiation resulting from a bar hold: Source

“We were looking forward to seeing her grow,” grandfather Jeffrey Kepner said.  “The cruise itself wasn’t what made me excited. It was the fact that I was gonna get to spend another week with my youngest son and his family and all the grandkids.”

The FBI on Sunday continued to decline to comment on the ongoing investigation, and ABC News has not independently confirmed the details of Anna’s death.

‘No such thing as steps’

The Kepners, their son, his three children, including Anna, his new wife, and her children from a previous marriage, took the trip together. It was to be a new tradition they were looking forward to keeping, Jeffrey Kepner said. The three generations had three staterooms on the ship.

“The two younger girls stayed with the parents and then the three teenagers, they decided amongst themselves they wanted to stay in the room together. But 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,” Barbara Kepner said.

The grandparents of the 18-year-old who was found dead on a cruise ship sit down with ABC News.
ABC News

The Kepners painted a picture of a happy group, where familial ties reached further than blood, and there’s “no such thing as steps” for siblings.

“It’s all family. It’s a blended family, yes, but that’s not how our family is,” Jeffrey Kepner said. “Our dynamic is we’re all just family.”

When Anna’s father remarried, the Kepners said they gained two new grandchildren.

Teen who died on Carnival cruise was found under bed, stepbrother under investigation: Source

“I loved them just like I’ve loved the rest of my grandchildren. They called us Memaw, Peepaw, told us they loved us,” Mrs. Kepner said.

“They were just like brother and sister,” Barbara Kepner said of the stepbrother now called a “suspect” in Anna’s death, according to court papers filed by his mother and Anna’s father in an unrelated matter.

Anna’s grandmother described the two teens as having been “two peas in a pod.”

“I know that those two kids cared about each other in the right way,” Barbara Kepner said. “I can’t accuse him because I don’t know what happened in that room.”

No formal charges have been filed.

Anna Kepner, 18, pictured here getting ready in her cruise ship room, was found dead on the Carnival Horizon as she was spending a holiday with eight members of her blended family.
ABC News

Anna’s grandparents said authorities told the family that the stepbrother, according to security cameras, was “the only one seen going in and the only one seen going out” from the room he had been sharing with Anna.

Kepner said she couldn’t understand why anyone would do such a thing to Anna — and wants to see justice done.

“That will be for the courts to decide,” Kepner said.

The Miami-Dade Medical Examiner’s office declined to comment Friday. The Kepners said the family has been told preliminary information indicates that there were no signs of sexual assault and that there did not appear to be drugs or alcohol in Anna’s system.

Autopsy and toxicology reports that could confirm those details have not been completed.

‘I couldn’t stop screaming’

The last night her grandparents saw Anna alive, her dental braces had been bothering her at dinner, Barbara Kepner said. But Anna was still determined to join in the fun.

“She just said, ‘Meemaw, I think I’m gonna go back to my room for a little bit, I don’t feel well.’ And she must have felt better, because she got dressed up. And she came down, we were playing in the casino. And she sat down and she played $20. And she didn’t win anything. And she said, ‘Meemaw, I love you guys, I’ll see you later,’” Mrs. Kepner said. “She’d pop in and out to check in with us. And we never saw her again after that.”

The next morning, Jeffrey Kepner said he was buying bingo cards when a medical alert blared over the ship loudspeakers. He recognized the room number.

“I went blank,” Jeffrey Kepner said. “I was hoping that it was something minor.” Instead, what he saw when he walked in haunts him. “I still wake up seeing that,” he said.

Anna’s body was discovered by a room attendant “concealed under the bed,” and there were bruises on the side of her neck, according to the Kepners and a security source briefed on the investigation.

When her son — Anna’s father — entered the room, Barbara Kepner said, “all he had to do was look at her and he knew she was gone. And then my husband got there and pulled them out of the room. As he said, they cannot see what they saw.” Then her husband came to tell her what had happened.

“I knew when he walked in the room, something was wrong,” Mrs. Kepner said. “And all he could say to me was, ‘Anna.’ The last I can remember for probably hours that morning is I just screamed. I couldn’t stop screaming.”

The utter shock of the situation hasn’t left much room for grief yet, the Kepners said — but it has made them crave understanding and rack their brains for clues.

“Those are the questions that we’ve been asking — what did we miss?” Mr. Kepner said.

Barbara Kepner said she thought Anna would have told her if she had any concerns about her safety.

“With my grandchildren, I have one rule, and it’s the only rule I have with all of them. You be truthful with me, I’ll be truthful with you, and we’ll figure this out,” Kepner said.

She said on the ship, the stepbrother told her, “In his own words, say he does not remember what happened.” She added, “I believe, to him, that is his truth.”

The stepbrother was questioned along with other family members by law enforcement — who also pored over the ship’s security camera footage and access-card swipes to get a picture of who was where at the various times prior to the death, according to the Kepner family and a security source briefed on the investigation.

“He was an emotional mess. He couldn’t even speak. He couldn’t believe what had happened,” Mrs. Kepner said of the stepbrother. After the boat docked in Miami, the stepbrother was hospitalized for psychiatric observation and then released to stay with a family member, Kepner said.

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Appearing virtually in a Florida family courtroom in connection with an unrelated custody matter connected to the divorce of Anna’s stepmother and her former husband, the attorney for Kepner’s stepmother told the court Thursday that, immediately after the incident on the cruise ship, the stepbrother was “hospitalized.” He has since been released from the hospital and is now living with a relative of the mother and receiving counseling, the lawyer said.  The lawyer did not explain the reason for the hospitalization.

“The biggest question that I want answered is the why. And that’s the answer that I don’t know if we’ll ever get,” Jeffrey Kepner said.

Along with the pain of the unknown, the grandparents said, has also come the feeling they’ve lost not one, but two kids they cared for.

“I now know how she died. It helps a little bit, but it’s not going to bring Anna back,” Barbara Kepner said. “No matter what we find out, no matter what they tell us, it’s not going to bring either one of these children back.”