Brianna Minnich, nine, spends each night tucked up in bed beneath the UV lights she needs to help battle the rare disease which can sometimes lead to brain damage.



Her skin and eyes turn yellow whenever she has a sudden change in mood caused by illness, injury, stress, being bullied at school or even arguing with her brother.







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Brianna, from Whitehall, Pennsylvania, suffers from Crigler-Najjar syndrome, a rare illness that only around 200 patients in the world - and just a handful in the US - suffer with.



The condition means she has dangerously high levels of bilirubin, a naturally occurring waste product from the blood usually broken down by an enzyme in the liver.



Currently Brianna has to sleep under a 4ft bank of phototherapy lights over her bed. But as she gets older it's likely she'll need a liver transplant which can cause complications.



The UV rays from the blue light affect the bilirubin in her system when they come into contact with her red blood cells and skin tissue.



By helping to manage bilirubin levels in her body and keep them at an acceptable level, Brianna is saved from any long term damage.



Her dad Bob, 29, said: "Her bilirubin levels were considerably high, right up in the high twenties for the first month or so after being born.



"We were told soon after the diagnosis that she was only the 52nd person in the country to have the disorder and just the 212th in the world.



"In the past three or four years her body has maintained a much more steady level of around 10-15 - the average person has a level of around 0.5 so it's still very high.



"She was started on Phenobarbital immediately, and used what was called a 'bili blanket' which is a small phototherapy blanket until she grew out of it.



"Whenever she is unwell and believe it or not whenever she has a sudden change in her mood such as getting upset at her brother or if she gets bullied then her skin tone changes drastically to a much more visible 'yellow' until she calms herself back down.



"She also sleeps under a 4ft long bank of phototherapy lights every single night, for at least 9 hours a night which typically keeps her skin tone fairly 'normal'.



"The only thing you can really see is her yellow eyes - people ask us all the time 'why are your daughter's eyes yellow?"



After being born Brianna underwent tests and was constantly in and out of the hospital for two weeks before finally being transferred to the Children's Hospital of Philadelphia.



She was eventually diagnosed with Crigler-Najjar syndrome at two-and-a-half weeks old and spent the best part of a month in hospital before being released.



Phototherapy has helped bubbly Brianna however the treatment becomes less successful as she grows up so her dosage of phenobarbital must increase.



The daily medication helps jump start her liver but whenever the dosage is increased it causes her to feel lethargic for weeks and constantly falls asleep at home and school as well as leaving her feeling depressed.































































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