A "darling" three-year-old girl with a unique combination of illnesses desperately needs a bone marrow transplant to save her life, doctors have said.
Tia Pugh, who loves Peppa Pig and the Muppets, has an extremely rare form of immune deficiency called STAT1 deficiency.
Medics have also discovered she has a tuberculosis-like illness called mycobacterium malmoense. They believe she may be the only person in the world to suffer both illnesses at the same time.
After months of hospital treatment and numerous tests, doctors now say her only chance of cure is a bone marrow transplant.
Tia's father Nick is from Worcester and her mother Yupa is Thai with Cambodian heritage. This relatively rare ethnic mix means finding a genetic match for Tia could prove extremely difficult.
Mr Pugh said: "Tia is our darling little daughter and it is heartbreaking to watch her suffer like this.
"Now that the doctors have identified what's wrong we can at last get moving on finding a cure.
"But we have to be quick, and that cure is out of our hands until we can find a match.
"All I can say to the people out there is please help us however you can, by signing up to the register or setting up a recruitment event in your area.
"Think how you would feel if it was your daughter, or your son, and you needed a stranger to help them survive. Childhood is supposed to be full of fun and joy, and that's all we want for our Tia.
"Please help us help her, by signing up to the bone marrow register."
The family lives in Worcester and have spent months in and out of hospital hoping to find a solution for Tia. The little girl underwent a blood transfusion before she was two and doctors have tried various combinations of medicine to make her better.
For months, Tia had to go to the hospital at 7am and 11pm every day to receive vital drugs and nurses visit her home daily at 11am and 3pm to help care for her.
Tia's mother has also undergone training to administer antibiotics to the little girl at home.
Tia, who loves singing and dancing to Peppa Pig, the Muppets' Mahna-Mahna song and Fatboy Slim's Eat, Sleep, Rave, Repeat when she has the energy, is also fed through an intravenous tube each night.
Anthony Nolan, which manages the bone marrow register, is urging people to sign up as donors, especially those of South East Asian and mixed-Asian heritage.
Henny Braund, chief executive of Anthony Nolan, said: "Tia's situation is so difficult that it's hard to hear about.
"But it is precisely this kind of circumstance that Anthony Nolan was set up to help with. Over the last 40 years we have seen thousands of caring, selfless people put their names on the register and thousands of lives have been saved as a result.
"Now it is vital that we get the message out, especially to the South East Asian community, so that we can find a match for Tia as soon as possible. Please help however you can."
Every year in the UK, around 1,800 people in the UK need a bone marrow or stem cell transplant. This is usually their last chance of survival.
White northern Europeans have a 90% chance of finding a suitable bone marrow donor but this falls to 40% for people from black, Asian, and ethnic minority backgrounds.
Some 90% of donations take place during an outpatient appointment that is similar to donating blood.
People can join the bone marrow register at www.anthonynolan.org/8-ways-you-could-save-life/donate-your-stem-cells/apply-join-our-register
Tia also has a dedicated Facebook page at www.facebook.com/pages/Tia-Pugh-immune-deficiency/249924451836434?ref=stream
Mr Pugh is 40 and his wife is 27.