24-year-old identical twin dies 1 month after being given ‘6 months to live’ amid terminal diagnosis

Caitlin Leggett, a 24-year-old from Cardiff, Wales, was told she had terminal cancer and had been given about six months to live. Her family hoped urgent treatment abroad might still give her a chance, but Caitlin died only a month after receiving that devastating prognosis.

Caitlin had first been diagnosed in April 2025 with acute myeloid leukaemia, an aggressive cancer affecting the white blood cells. She went through chemotherapy and reached remission, then later received a stem cell transplant. For a time, there was hope that the treatment had worked. But in May, her family learned that the cancer had come back.

Because doctors in the UK were unlikely to offer treatment that could cure her, Caitlin's loved ones began raising money for overseas medical care. Her twin sister, Grace, explained the urgency on GoFundMe, writing that they had just celebrated their 24th birthday and that without urgent treatment abroad, it would be Caitlin's last. Grace said Caitlin's only chance of a cure depended on raising enough money to support medical treatment outside the UK.

Grace and Caitlin were more than sisters. They were best friends, had always been close, and had even lived together while at university. Their bond became even more significant after Caitlin's diagnosis, when a medical discovery changed what the family had always believed about them.

For years, Caitlin and Grace had been thought to be fraternal twins because they developed in separate amniotic sacs. When doctors assessed Grace as a possible stem cell donor, tests showed that the sisters shared the same genetic markers. They were, in fact, identical twins.

The discovery was astonishing, but it also brought heartbreaking consequences. Because their DNA was nearly identical, Grace could not donate stem cells to Caitlin. The person closest to her in every way was no longer an eligible donor.

Grace described the shock of facing that reality at such a young age, saying that at 24 no one expects something like this to happen, and that twins are not meant to face a future where one of them is no longer there. Caitlin also spoke of how impossible it felt, saying they had gone through life together and she did not want their story to end there.

The family continued to hope and seek help, but Caitlin's health declined suddenly. On June 16, Grace shared that Caitlin had passed away the previous day. In her GoFundMe update, she wrote that Caitlin had suffered a sudden and serious brain bleed, followed by a series of strokes that caused a rapid decline.

Caitlin died peacefully while surrounded by the love and care of her family. Grace thanked everyone for their love and support during such a painful time.

Caitlin's story is remembered as one of deep family devotion, urgent hope, and the cruel limits that illness can place on even the closest bond. She had fought through treatment, remission, relapse, and the search for another chance, while her family and twin sister did everything they could to help her. Her final days ended with her loved ones beside her, and her memory remains with those who knew and supported her.