The granddaughter of former US President John F Kennedy has announced her diagnosis with an aggressive form of cancer.

Tatiana Schlossberg said she has been given less than a year to live.

The 35-year-old shared the news in an essay published in The New Yorker on Saturday, the 62nd anniversary of her grandfather's assassination.

The mother-of-two climate journalist has been an outspoken opponent of her relative Robert F Kennedy Jr's position as US health secretary under President Donald Trump.

In her essay, Schlossberg describes her alarm at watching her cousin be approved for the post as she was battling her illness.

Schlossberg is the daughter of designer Edwin Schlossberg and diplomat Caroline Kennedy. She is the granddaughter of John F. Kennedy, the 35th president of the United States, and First Lady Jacqueline Kennedy Onassis.

According to Schlossberg's essay titled A Battle With My Blood, she was diagnosed with acute myeloid leukaemia after giving birth in May 2024.

She described her previously healthy lifestyle, which included running, skiing, and even once swimming in New York's Hudson River, "eerily, to raise money for the Leukaemia and Lymphoma Society".

Despite treatment, including a bone marrow transplant and chemotherapy, she said doctors have told her the outcome does not look good.

"During the latest clinical trial, my doctor told me that he could keep me alive for a year, maybe," she writes.

"My first thought was that my kids, whose faces live permanently on the inside of my eyelids, wouldn't remember me."

Schlossberg's son was born in 2022 and her daughter in 2024.

Schlossberg, whose uncle John F Kennedy Jr died in a plane crash at age 38 and whose grandmother Jacqueline died of cancer when Schlossberg was a toddler, also describes the pain she fears her death will cause her mother, who previously served as US ambassador to Australia and Japan.

"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 writes.

"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."

She also described her upset at watching her cousin, known as RFK Jr - whose father Robert F Kennedy was also assassinated while running for president - become Trump's health secretary.

"I watched from my hospital bed as Bobby, in the face of logic and common sense, was confirmed for the position, despite never having worked in medicine, public health, or the government," she writes.

"Suddenly, the healthcare system on which I relied felt strained, shaky."

Earlier this month, her brother Jack Schlossberg announced that he is planning to run for Congress in New York.

He shared her essay online on Saturday, with the caption: "Life is short - let it rip."

The Kennedy family's generations-spanning participation in US politics - along with the personal tragedy which has often touched its members - has garnered it a prominent reputation in American life.