The morning before Caitlin Leggett went into hospital for the last time, she tried on bridesmaids’ dresses with her twin Grace and their younger sister Neve. A wedding was coming up, with Caitlin due to be maid of honour for her father’s partner. “She mentioned to a couple of people that she was the happiest that she’d ever been in her last two weeks,” Neve said.
Caitlin was 24. At 2.42am on June 15 she died, a few weeks after her family began raising money for treatment that might have saved her.
A rash, then a surprise
The story begins in March 2025 with a rash that would not clear. Caitlin had been due to take a medical assessment for the Army the following month, with plans to train as an intelligence officer. Instead came blood tests and an order to report next day to the Cardiff hospital unit run with Teenage Cancer Trust. The diagnosis, in April 2025, was acute myeloid leukaemia, an aggressive cancer of the white blood cells.
She needed a stem cell transplant, so doctors assessed Grace as a possible donor. They found something nobody expected. The sisters had always been told they were fraternal, partly because they grew in separate amniotic sacs, yet their markers matched exactly. They were identical twins. It was a shock, and it was also a setback: with near-identical DNA, Grace could no longer donate.
Remission, and a return
The treatment path was long. Chemotherapy brought remission in May 2025, but by August the cancer had reappeared in her skin. A clinical trial in Manchester using menin inhibitors pushed it back again. A week before her planned transplant the disease returned to her skin once more. She went ahead in December 2025 after extra full-body radiotherapy, and in January 2026 she was told she was in remission.
Caitlin pushed for an extra bone marrow check in May, because she did not feel safe moving to less frequent tests. It found the leukaemia had come back. Doctors told her that UK options were unlikely to cure her and that a second transplant could not be done in Britain. On her current plan she had about six months.
“Nobody expects this to happen,” Grace said. “You’re not supposed to have one twin not be there.”
The fundraiser
The family looked abroad, most likely to the US, where treatment and associated costs could reach £500,000. A GoFundMe page went up on June 2, and by June 10 it had passed £100,000. On Saturday June 13 Caitlin suffered a sudden, serious brain bleed, followed by a series of strokes. She declined fast.
Around her bed were Grace, her brother Ethan, 27, Neve, 19, and her parents, Jennifer, 54, and Ian, 57. “We all got the chance to speak to her,” Grace said. “Neve put her favourite pillow spray on, we massaged her hands with lotion, and the nurses gave us a memory box with special paper and a charcoal wipe, so we could take her footprints and hand prints.” Grace played piano, and music by her sister’s favourite pianist, Patrik Pietschmann, played from a speaker as Caitlin died peacefully.
Grace had once feared her sister dreaded a slow death. “So I’m just really grateful that it was really quick, and she didn’t know,” she said. Her father Ian remembered Caitlin’s “fighting spirit” and her outlook that “if it’s not OK, it’s not the end.”
On June 27 the family paused the fundraiser at £127,722. Part of it will go to Teenage Cancer Trust, to fund a lead nurse overseeing the service in Cardiff and South Wales for a year, and part to Leukaemia UK for a research grant.
Sources
- Identical Cardiff twin dies weeks after setting up leukaemia fundraiser – BBC News
- Cardiff woman with acute myeloid leukaemia says leaving twin is 'unthinkable'
- Woman, 24, dies of leukaemia while fundraising for life-saving treatment | The Independent
