Can you put a price on a life? Leni has only six months before she loses her ability to live a healthy life. Her heartbroken parents have had to resort to crowdfunding.
Race to save two-year-old with dementia
Heartbreaking reality: Most children are not diagnosed until they are older and show symptoms, but one of Leni's parents found out they were a carrier of the faulty gene, and so Leni was tested early. Glossary
Sanfilippo syndrome - A rare genetic disorder. A change in a single gene means a child's body is unable to break down certain sugars. Children often experience a decline after the age of two, eventually leading to death.
Dementia - A syndrome associated with memory loss and other declining brain functions.
Clinical trial - A carefully designed study with human volunteers, used to work out whether a new medicine is effective and safe.
GoFundMe - An American crowdfunding website. People use it to raise money for things ranging from celebrations to medical treatments.
NHS - The National Health Service, the publicly funded healthcare system in the UK. The NHS was founded in 1948.
Monetary - Relating to money.