Given that the author has been dead for years and the Internet is forever, Roald Dahl’s letter urging people to vaccinate their kids isn’t exactly hot news. The letter was written in 1988 and has been on Dahl’s site for some time, but it has understandably surfaced again this week, given the recent “everyone at Disneyland has measles now” kerfuffle. The Daily Dot has an especially interesting look at the letter written by Ned Donovan, Dahl’s grandson, which talks about the visits his family would take to the cemetery to visit his late aunt, Roald Dahl’s daughter. She caught measles and died in 1962, just a few years before the vaccine became readily available. The entire process was quick and brutal, with Dahl writing, “in an hour, she was unconscious. In 12 hours she was dead.”

Dahl also encourages “all school-children who have not yet had a measles immunization” to “beg their parents to arrange for them to have one as soon as possible,” noting that “in a district of around 300,000 people, there will be only one child every 250 years that will develop serious side effects from measles immunization.”