Maria Shriveris mourning her cousin and friend,Tatiana Schlossberg.
Shriver – who is the cousin of Schlossberg's mother,Caroline Kennedy– paid tribute to Schlossberg, whom she called "sweet, beloved" as well as "valiant, strong" and "courageous."
"I return to this space to pay tribute and honor her loving and supportive family, who came together and did everything they possibly could do to help her," Shriver, 70, captioned acarousel of Instagram photosof Schlossberg, including a New Yorker photo with her hair short and styled in a graying pixie cut. "I return to this space heartbroken because Tatiana loved life. She loved her life, and she fought like hell to try to save it."
Schlossbergdied at 35, the John F. Kennedy Library FoundationconfirmedDec. 30. The news came after she revealed a terminalcancerdiagnosis ofacute myeloid leukemiaina heart-wrenching essayfor the New Yorker published Nov. 22.
Caroline Kennedy's daughter Tatiana Schlossberg, 35, has died after revealing her terminal cancer diagnosis in a New Yorker essay published Nov. 22. See the granddaughter of former U.S. President John F. Kennedy's life in photos, beginning here at the 2023 Profile in Courage Award ceremony at the John F. Kennedy Library in Boston, Oct. 29, 2023." style="max-width:100%; height:auto; border-radius:6px; margin:10px 0;" loading="lazy" /> 
Tatiana Schlossberg, Caroline Kennedy's daughter, dies. See her career
Caroline Kennedy's daughter Tatiana Schlossberg, 35,has diedafter revealing her terminal cancer diagnosis in a New Yorker essaypublished Nov. 22. See the granddaughter of former U.S. President John F. Kennedy's life in photos, beginning here at the 2023 Profile in Courage Award ceremony at the John F. Kennedy Library in Boston, Oct. 29, 2023.
Tatiana Schlossbergand the curse of tabloid cruelty
"She will always be in our hearts," her parents, siblings, husband and childrensaid in an Instagram post.
Schlossberg is President John F. Kennedy's granddaughter, while Shriver's mother is Eunice Kennedy Shriver – the sister of the former president, aunt of Caroline Kennedy, 68, and great-aunt of Schlossberg.
"I cannot make sense of this. I cannot make any sense of it at all. None. Zero," Shriver continued. "Tatiana was a great journalist, and she used her words to educate others about the earth and how to save it. She created a beautiful life with her extraordinary husband George, and children Eddie and Josie. She fought like a warrior."
Tatiana Schlossberg,John F. Kennedy's granddaughter, has died
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Shriver recalled growing up with Schlossberg's mother, Caroline Kennedy, and their other cousins, calling her a "rock" amid the loss.
Shriver also encouraged her followers to read Schlossberg'sNew Yorker essay. "Her piece is extraordinary. Whatever your faith, please pray for Tatiana and her grieving family."
In the essay, Schlossberg wrote that she learned she hadacute myeloid leukemiaafter giving birth to her second child in May 2024, and her doctor noticed an imbalance in her white blood cell count. She described how she handled the diagnosis with her family. She said she tried to stay present with her children even when it was difficult.
"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 wrote. "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."
Shriver called the journalist "a perfect daughter, sister, mother, cousin, niece, friend, all of it." She added: "Those of us left behind will make sure (her children) Eddie and Josie know what a beautiful, courageous spirit their mother was and will always be. May we all hold Tatiana's family in our collective embrace not just today, but in the days ahead."
Contributing: Sarah D. Wire and Nicole Fallert, USA TODAY
This article originally appeared on USA TODAY:Tatiana Schlossberg death: Maria Shriver mourns cousin