Tatiana Schlossberg, the daughter and middle child of Caroline Kennedy and Edwin Schlossberg’s three children, died on Tuesday. She was 35.

The granddaughter of former President John F. Kennedy’s immediate family announced her death with a brief note on the Instagram account of the JFK Library Foundation.

“Our beautiful Tatiana passed away this morning. She will always be in our hearts,“ read the message, which is noted to be from “George, Edwin and Josephine Moran, Ed, Caroline, Jack, Rose and Rory.”

In her career, Schlossberg worked as a science and climate reporter for The New York Times and wrote for outlets including The Atlantic, The Washington Post, Vanity Fair and Bloomberg. She also authored a book, Inconspicuous Consumption: The Environmental Impact You Don’t Know You Have. Schlossberg was a graduate of Yale University and the University of Oxford.

Schlossberg announced in an article in the New Yorker in November that she was diagnosed with acute myeloid leukemia, which was discovered during her daughter’s birth in May 2024, her second child. During childbirth, her doctor noticed that her white-blood-cells per microliter count was far under what is considered normal, she wrote. Treatment required months of chemotherapy and a bone-marrow transplant.

Schlossberg wrote of being wheeled away from her newborn child to another floor of the hospital after giving birth for testing following the discovery, and eventually, spending five weeks at Columbia Presbyterian Hospital in Manhattan. She was able to undergo at-home treatment before being admitted to Memorial Sloan Kettering Hospital. Her sister, Rose, was a match for a transplant of stem cells. After the transplant, the cancer went into remission but soon relapsed. 

“My brother was a half-match, but he still asked every doctor if maybe a half-match was better, just in case,” she wrote.

At the beginning of this year, Schlossberg began a clinical trial of CAR-T-cell therapy, a type of immunotherapy that involved the engineering of her sister’s T cells to attack the cancer. This was later repeated with an unrelated donor. Her cancer went into remission again, but as she wrote, she was hospitalized twice — once for graft-versus-host disease and in late September, a form of Epstein-Barr virus.

In the New Yorker, she wrote of her family’s incredible support in the last year and a half of her life. 

“My parents and my brother and sister, too, have been raising my children and sitting in my various hospital rooms almost every day for the last year and a half. They have held my hand unflinchingly while I have suffered, trying not to show their pain and sadness in order to protect me from it,” she wrote. “This has been a great gift, even though I feel their pain every day. For my whole life, I have tried to be good, to be a good student and a good sister and a good daughter, and to protect my mother and never make her upset or angry. Now I have added a new tragedy to her life, to our family’s life, and there’s nothing I can do to stop it.”