Tatiana Schlossberg, the youngest granddaughter of President John F. Kennedy, tragically died of cancer Tuesday at age 35, the JFK Library Foundation announced. 

“Our beautiful Tatiana passed away this morning. She will always be in our hearts,” the foundation posted on its Instagram page, with the note signed by “George, Edwin and Josephine Moran, Ed, Caroline, Jack, Rose and Rory” — referring to her husband, two small children, parents, two siblings and a sister-in-law.

Schlossberg, the daughter of Caroline Kennedy Schlossberg, had written a heart-wrenching personal essay published in the New Yorker magazine last month in which she revealed that she had less than a year to live after being diagnosed with myeloid leukemia with a rare mutation. 

“Maybe my brain is replaying my life now because I have a terminal diagnosis, and all these memories will be lost,” Schlossberg wrote in the piece published on Nov. 22 — the 62nd anniversary of her grandfather’s 1963 assassination.  

She agonizingly described the prospect of her children — Edwin, 3, and 19-month-old Josephine — growing up without memories of her. 

“My first thought was that my kids, whose faces live permanently on the inside of my eyelids, wouldn’t remember me. My son might have a few memories, but he’ll probably start confusing them with pictures he sees or stories he hears,” she wrote.

“I didn’t even really get to take care of my daughter – I couldn’t change her diaper or give her a bath or feed her.

“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,” Schlossberg said.

In January, she joined a clinical trial of CART-cell therapy, a type of immunotherapy against certain blood cancers but was then tragically given the terminal prognosis. 

Schlossberg leaves behind her doctor husband, George Moran, their two kids, and her parents, Caroline, 67, and Edwin Schlossberg, 80. 

She is also survived by her older sister Rose, 37, and younger brother, Jack, 32, as well as Rose’s wife Rory McAuliffe.

Jack Schlossberg who is running for Congress in the 12th Congressional District being vacated by Manhattan Rep. Jerold Nadler.

The liberal congressional hopeful, who has a history of controversial social-media posts, looked disheveled and puffy-eyed as he hurried his little nephew in a stroller into his late sister’s luxury Park Avenue apartment building after news of her passing broke. 

The Kennedy scion previously boasted about helping his sister raise her kids and being a devoted uncle, telling Today in 2022 that he prefers to call his nephew by his own name.

“His name is Edwin, but I like to call him Jack,” the Kennedy heir said to the news outlet, eagerly telling anchor Savannah Guthrie that he visits the little tyke every chance he gets.

“I can’t get away from him. I love him.”

In her personal essay, Tatiana had described how doctors discovered her cancer just hours after she gave birth to her daughter in May 2024. She spent the past 18 months in treatment, receiving a bone-marrow transplant, chemotherapy and blood transfusions. 

The rare mutation that Tatiana was diagnosed with – Inversation 3 – is generally seen in older patients. 

The married mom, who graduated from Yale and has a master’s degree from Oxford University, previously worked as a journalist at the New York Times and published her first book in 2019.

She has been married to Moran, a urologist who she met as an undergrad at Yale, since 2017.

Tatiana had written that her immediate family was helping her raise her two young children amid her treatment and described the heartbreak of adding further tragedy to her mother’s already turbulent life. 

“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,” she said.

“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.”

Her mother Caroline’s uncle, Robert F. Kennedy, was assassinated in 1968, fewer than five years after her father’s death. 

Caroline’s mother, Jackie Kennedy Onassis, also died in 1994 at the age of 64 during a short battle with non-Hodgkin lymphoma, which spread to her spinal cord, brain and liver. 

Caroline’s younger brother, John F. Kennedy, Jr., died in 1999 at age 38 in a plane crash that also killed his wife and Caroline’s sister-in-law, Carolyn Bessette Kennedy, 33, and Bessette Kennedy”s sister Lauren.