Jack Schlossberg is still struggling to wrap his head around the loss of his late sister, Tatiana Schlossberg.
Speaking to Vanity Fair in an interview published on Friday, May 15, Jack, 33, admitted, “I don’t think I’ll ever process it.”
Tatiana, who was the daughter of Caroline Kennedy and granddaughter of the late President John F. Kennedy — died in December 2025 after being diagnosed with terminal cancer. She was 35.
“The world will never be the same for me, not only since she passed away, but since she was diagnosed with cancer about two years ago,” Jack told Vanity Fair.
Jack, who is also a younger brother to Rose, 37, said his sister Tatiana is still on his mind almost five months after her death.
“She was my best friend. We could finish each other’s sentences,” Jack added. “I miss her all the time. Every day I think about her.”
The JFK Library Foundation confirmed Tatiana’s death following her battle with acute myeloid leukemia via an Instagram statement in December 2025.
“Our beautiful Tatiana passed away this morning. She will always be in our hearts,” the statement read. It was signed by Tatiana’s husband, George Moran, their two children, Edwin, 4, and Josephine, 1, her parents, siblings and sister-in-law Rory Schlossberg.
Tatiana Schlossberg. (Photo by Amber De Vos/Getty Images for goop)
In a New Yorker essay published in November 2025, Tatiana wrote that she had been given a year to live after receiving her devastating diagnosis.
Tatiana shared that she learned she had “a rare mutation called Inversion 3” after her doctor noticed an imbalance in her white blood cell count following the birth of her second child. Initially, Tatiana was told she would need to undergo months of chemotherapy and receive a bone marrow transplant.
“I did not — could not — believe that they were talking about me. I had swum a mile in the pool the day before, nine months pregnant. I wasn’t sick. I didn’t feel sick. I was actually one of the healthiest people I knew,” she wrote. “I had a son whom I loved more than anything and a newborn I needed to take care of.”
As Tatiana Schlossberg underwent stem cell treatment for her terminal cancer battle, her siblings leapt into action to help. “My sister had turned out to be a match and would donate her stem cells,” Tatiana, 35, wrote in a New Yorker essay published Saturday, November 22, referring to older sister Rose Schlossberg. “My brother [Jack […]
Tatiana added in the essay that her mind immediately went to her young children and she shared her fears that they would grow up with limited memories of their mother.
“My first thought was that my kids, whose faces live permanently on the inside of my eyelids, wouldn’t remember me,” she recalled. “My son might have a few memories, but he’ll probably start confusing them with pictures he sees or stories he hears. I didn’t ever really get to take care of my daughter — I couldn’t change her diaper or give her a bath or feed her, all because of the risk of infection after my transplants. I was gone for almost half of her first year of life. I don’t know who, really, she thinks I am, and whether she will feel or remember, when I am gone, that I am her mother.”