A four year old girl from Deal is only the 20th person in the world to have a rare genetic mutation that will end her life prematurely.
Lilly Day, of Lydia Road, has an uncommon variation of an already rare disease Ataxia-Telangiectasia, called MRE11.
This is a degenerative condition that causes increasingly severe disability. With classic A-T, most patients are wheelchair-bound by the age of 10 and die in their late teens.
Hayden with dad Joe and Lilly
Lilly, who goes to Hornbeam Primary School, has a form of A-T that is slower progressing and as she is only the ninth person in the UK to be diagnosed with a condition very little is known about.
Her father Joe Day, 37, said: "It's going to affect her everyday life dramatically. With a typical A-T patient, sadly the walking will peak at the age of four and a half which is where she is now.
"It's a deterioration from this point she will eventually lose the ability to walk, she will learn to read and write and then lose the ability to do that, and eventually lose the ability to swallow."
Mr Day's son and Lilly's half-brother - 15-year-old Hayden Day - will be taking part in the Boxing Day dip with other pupils from Castle Community College to raise money for the A-T Society, the charity that has been working closely with the family.
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