Two-year-old Isla is believed by medical experts to be the only person in the world living with a genetic condition that accelerates the ageing of her cells.
So little is known about it that even specialists do not know what her future holds and what support she might need.
Her parents Stacey Kilpatrick and Kyle Screaton told the BBC’s Victoria Derbyshire programme they are considering taking legal action against the hospital that treated her.
University Hospitals of Leicester NHS Trust said it was “very sorry Isla’s parents have concerns about her care in our hospitals. We urge them to contact us directly if they have ongoing concerns.”
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