Maria Shriver spoke out following the death of Tatiana Schlossberg at age 35.

“I return to this space today to pay tribute to my sweet, beloved Tatiana, who left this earth today,” Shriver wrote on Instagram on Tuesday, Dec. 30, alongside several photos of her late cousin. “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. I return to this space heartbroken because Tatiana loved life. She loved her life, and she fought like hell to try to save it.”

“I cannot make sense of this. I cannot make any sense of it at all,” Shriver wrote. “None. Zero.”

“Tatiana was a great journalist, and she used her words to educate others about the earth and how to save it,” Shriver continued. “She created a beautiful life with her extraordinary husband George, and children Eddie and Josie. She fought like a warrior. She was valiant, strong, courageous.”

Shriver, who is also a journalist and author, went on to praise Shlossberg’s mother, Caroline Kennedy. “What a rock she has been,” Shriver wrote of her cousin. “What a source of love she has been with Ed, Rose, Rory, Jack, George, Eddie, Josie, and all of Tatiana’s cousins and friends and the amazing doctors who tried so hard.”

Shriver, the daughter of Eunice Kennedy Shriver and Sargent Shriver, was the first cousin once removed of Schlossberg, who died Dec. 30, following a battle with acute myeloid leukemia.

Schlossberg, an accomplished environmental journalist, was the daughter of Caroline and Edwin Schlossberg, as well as the granddaughter of President John F. Kennedy.

Schlossberg’s family announced her death in a social media post from the JFK Library Foundation.

“Our beautiful Tatiana passed away this morning. She will always be in our hearts,” the post said.

It was signed by “George, Edwin and Josephine Moran, Ed, Caroline, Jack, Rose and Rory.”

Schlossberg was married to George Moran, with whom she had two children. In an essay published by The New Yorker in November, she revealed that she was diagnosed with cancer shortly after the birth of her daughter Josephine in 2024.

“I had swum a mile in the pool the day before, nine months pregnant,” she wrote. “I wasn’t sick. I didn’t feel sick. I was actually one of the healthiest people I knew.”

In her message on Tuesday, Shriver asked her followers to read Schlossberg’s “extraordinary” essay.

“Those of us left behind will make sure Eddie and Josie know what a beautiful, courageous spirit their mother was and will always be,” Shriver wrote. “She takes after her extraordinary mother, Caroline. May we all hold Tatiana’s family in our collective embrace not just today, but in the days ahead, and may each of you who read this know how lucky you are to be alive right now. Please pause and honor your life. It truly is such a gift.”

Schlossberg spent several years covering science and climate for The New York Times, having previously worked at The Record in New Jersey.

Shriver, a journalist and the former First Lady of California during her previous marriage to Arnold Schwarzenegger, is the first cousin of Caroline Kennedy.

Shriver’s mother, Eunice, was the younger sister of President Kennedy.