Progeria campaigner Hayley Okines, who became known as the “100-year-old teenager”, has died aged 17.

Hayley Okines was born with Progeria, a rare condition that caused her body to age eight times faster than normal.

The rare ageing disease usually debuts within the first two years of birth, when symptoms such as slow growth and hair loss began to appear. The average life expectancy for a child with the disease is just 13, but Hayley Ikines defied all odds and lived for another four years.

Hayley Okines of Bexhill-on-Sea, England, became a spokesperson and fundraiser for progeria and campaigned for greater awareness throughout her teens. She released her autobiography at the age of 14, entitled Old Before My Time.

The girl had been treated in hospital for pneumonia over the past few days and returned home on April 2. She died on the same day, the BBC reported.

Hyaley’s mother, Kerry Okines, confirmed her death on Facebook, writing: “My baby has gone somewhere better. She took her last breath in my arms at 9.39pm.”

Progeria Research Foundation also paid an emotional tribute to Hayley Okines on its Facebook page: “The entire Progeria family mourns together with many as we say goodbye to Hayley Okines, our smart, beautiful and spirited English Rose.”

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