Credit: Ronald Dumont/Daily Express/Hulton Archive/Getty Images

In 1962, Roald Dahl’s daughter, Olivia, died of measles—and Dahl coped with her death by writing about it, according to an excerpt from Donald Sturrock’s Storyteller: The Life of Roald Dahl published in The Guardian.

An outbreak of measles struck Olivia’s school, and there wasn’t yet a vaccination for the disease available in England where the Dahls lived so Dahl’s wife turned to her brother-in-law, who lived in America at the time, to procure preventative medicine. He did—but only enough for Theo, the Dahl’s young son. “Let the girls get measles,” he said. “It will be good for them.”

Unsuprisingly, measles wasn’t good for them: Seven-year-old Olivia died in the hospital after she became unconscious at home. “Doctor said to nurse go out. Leave him alone,” Dahl wrote in a straightforward note recounting his daughter’s death. “I kissed her. She was warm. I went out.”

Dahl’s reliance on writing through times good and bad is a theme that runs through the excerpt, which also details his son Theo’s struggles after an accident almost left him with serious brain damage. And though the note Dahl wrote about his daughter’s death was stowed away, he penned a piece 24 years later for a public health pamphlet that urged parents to get their children vaccinated.

“There is today something that parents can do to make sure that this sort of tragedy does not happen to a child of theirs,” he wrote in the article, obtained by Vox. “They can insist that their child is immunized against measles.”

This piece made the internet rounds Monday after New Jersey governor Chris Christie told reporters that his children are vaccinated but he understands “that parents need to have some measure of choice in things as well.” His statement was met with much scruntiny, especially because of the ongoing measles outbreak going on in the United States that was first linked to California’s Disneyland theme park in early January.

Read the book excerpts, which also highlights the writer’s interest in medicine and his relationship with his wife, over at The Guardian.