"No habrían soportado que se supiera lo de los Potter."

"No habrían soportado que se supiera lo de los Potter."
 

I've begun translating Harry Potter and the Sorcerer's Stone per Chileno's popular suggestion that one translate a Spanish novel into English to improve one's reading skills and vocabulary. It seems to be a very popular choice among Spanish students for its relative simplicity, brevity, and familiarity. I've encountered a very confusing clause rather early. It's emboldened in the quote below.

"Los Dursley tenían todo lo que querían, pero también tenían un secreto, y su mayor temor era que lo descubriesen: no habrían soportado que se supiera lo de los Potter."

In the American English version, (I include the word American because the American and British versions of the book are published under different titles and I'm unsure if they're otherwise entirely identical) the seemingly correspondent sentences are: "The Dursleys had everything they wanted, but they also had a secret, and their greatest fear was that somebody would discover it. They didn't think they could bear it if anyone found out about the Potters." My original translation of the first sentence in the paragraph above was nearly identical. It was: "The Dursleys had everything they wanted, but they also had a secret, and their greatest fear was that it would be discovered."

I've read two threads on other websites about this very clause, but the responses were somewhat ambiguous. As a superficial translation of the clause yields a rather nonsensical statement (something like, "they would not have tolerated that was known it of the Potters,") I'm hoping that someone can offer some insight and perhaps alternative examples of constructions of this sort.

In this case, 'lo' is used to make what follows it a noun (a noun clause). 'About the Potters' is a great translation of the more literal 'the thing about the Potters'. Don't forget that 'de' has more than one meaning.

Hablamos de los Potter. = We're speaking about the Potters.
¿Y? = What about them?
Hombre, lo de los Potter. = You know, about the Potters. (a reference to whatever news you've found out about them)

'They would not have tolerated others finding out about the Potters.'

Thanks Rusty, that makes things much more clear.