Judy steps up next to Joanne and Hadley Freeman tells us about it. Power trio!

You can try to explain Judy Blume in numbers: her books for children have sold 90 million copies worldwide, most famously Are You There God? It’s Me, Margaret. Over a 54- year career she has won more than 90 literary awards and been translated into 32 languages.

But this doesn’t explain her impact on generations of children, particularly girls. Blume, more than any other author before or since, taught kids about masturbation (in Deenie), menstruation (. . . It’s Me, Margaret) and sex (Forever). She reassured them that hating your younger sibling sometimes is normal (Tales of a Fourth Grade Nothing) and that terrible things can happen to good kids and they’ll survive (Tiger Eyes). Most of all she taught them that it’s fine to be exactly what they are: ordinary kids.

There’s a new movie adaptation of It’s Me, Margaret.

I tell Blume how strangely thrilling it is to see a movie about children where none of them are in possession of magical powers. “Yes, children are so used to superheroes now, aren’t they?” she says. Even in JK Rowling’s Harry Potter books the kids are magic, and I love those, I say.

“And I love her,” Blume immediately interjects. “I am behind her 100 per cent as I watch from afar.” Blume is referring to the abuse Rowling has received for speaking up in defence of women’s sex-based rights, and given that Blume has faced repeated attacks since the 1980s, for her books’ descriptions of adolescent sexuality and puberty, she knows what it’s like to be pilloried as an author.

Why was she pilloried?

[The movie] also keeps in all the details — adolescent lust, the chat about menstruation, Margaret’s anxieties about religion — that have caused the book to be attacked multiple times by right-wing religious groups, alongside other Blume books for similar reasons. Blume has long been a courageously punchy critic of these groups, and just the day before she and I talk it was reported that Florida politicians are considering a ban on any discussion of menstruation in schools’ sex education before the 6th grade, when children are 12.

Well you can see their point. If you teach kids about menstruation when they’re 10 they might just start doing it right then and there.

“It’s so bad. If it was bad in the 1980s, this is triple quadruple that, because this time it’s coming from the government, who are making laws. They say they want to protect kids, but it’s more like they want them to not think or ask questions,” she says.

It’s strange how the attacks on you have come from the right, whereas the ones on Rowling have come from the left, I say.

But a strange, twisted, upside-down version of the left, that believes in magic and detests women.