Weeks after doctors brushed off her daughter's symptoms as flu, Rachel Catterall watched as Daisy succumbed to a rare condition she had never heard of.
When 25-year-old Daisy called her mother in early 2025 to report swollen glands in her neck, both thought little of it. Her flu-like signs triggered haemophagocytic lymphohistiocytosis, a life-threatening disorder where an overactive immune system attacks organs and blood cells.
Rachel, a painter and decorator from Cirencester, knew nothing of the illness before her daughter died at 25 and now shares the story to raise awareness.
"I was watching the doctors work on her when they said she couldn't be saved," the 55-year-old mother of three told Sun Health.
"I could see they were right. Her body had been ravaged by this hideous disease."
"Basically, her own body was killing her. When they called time, I was absolutely devastated."
"I could see there was no chance for her, though. It all happened in the blink of an eye."
Daisy worked for the local council and recently bought her first home with her 27-year-old boyfriend, Matty. They traveled globally while planning a wedding and family. As an avid gym attendee, her mother noted she was extremely fit and never ill.
When Daisy reported feeling unwell in January 2025, Rachel thought little of it. Doctors diagnosed a viral infection and prescribed antibiotics.
Rachel stated, "Over the next few weeks, she was back and forth with them. She had gotten over the swollen glands, but then the achey joints started, as well as rashes. They all said it was the same thing and that she had nothing to worry about."
Before a planned trip to Cambodia and Vietnam with husband Sam, also 55, Daisy entered the hospital with abnormal blood counts. She insisted her parents take the trip, leaving the hospital the day before their departure as an outpatient.
Two days into the holiday, they learned Daisy returned to the hospital. During a FaceTime call, a consultant requested a bone marrow biopsy, prompting Rachel to seek flights home.
Upon returning to the UK, Daisy sat in critical care receiving medication. Doctors diagnosed the rare condition, and early the next morning, kidney failure required dialysis and an induced coma.
Rachel said, "We told Daisy they were going to put her to sleep and when she woke up, she would be going to the Philippines. Staying positive while telling her this, when inside I was devastated, was the hardest thing I've ever done."
Daisy suffered a cardiac arrest and died at 9am on February 22, 2025. Family and friends created "Daisy's People" to raise funds for University College London Hospital, collecting £86,000 so far. Over 500 people attended her funeral, and her ashes are being scattered worldwide.
What is haemophagocytic lymphohistiocytosis?
Haemophagocytic lymphohistiocytosis is a rare immune disorder where the body reacts inappropriately to a trigger, usually an infection. Specialised white blood cells become over-activated, causing severe inflammation and tissue damage.
Symptoms include rashes, high temperature, swollen organs, anaemia, infection, bruising, bleeding, seizures, wobbliness, and drowsiness. Diagnosis is difficult because signs mimic other conditions. The NHS notes it affects roughly 100 people in the UK yearly, and proves fatal in about 50 per cent of cases without swift treatment.
