Olivia Dahl (died 1962)

Olivia Twenty Dahl was the oldest child of the author Roald Dahl and the American actress Patricia Neal. She died at the age of seven from encephalitis caused by measles, before a vaccine against the disease had been developed. Roald Dahl's books James and the Giant Peach (1961) and The BFG (1982) were dedicated to Olivia. As a result of her death, her father Roald became an advocate for vaccination and wrote the pamphlet "Measles: A Dangerous Illness" in 1988.