How does Petunia know about Dementors?

[potioncat]

No: HPFGUIDX 97163


> Geoff:
> Most certainly /not/ in Little Whinging.
> 
> 'The Dursleys had everything they wanted but they also had a secret 
> and their greatest fear was that somebody would discover it.
snip
 in fact, Mrs.Dursley pretended she didn't have a 
> sister because her sister and her good-for-nothing husband were as 
> unDursleyish as it was possible to be. the Dursleys shuddered to 
> think what the neighbours would say if the Potters arrived in the 
> street.'
> 
> (PS "The Boy Who Lived" p.7 UK edition)
> 
> So, right at the very beginning of the story, we know that there is 
> an estrangement and, even in 1981, the family hadn't met for years. 
> One gets the impression that the Dursleys had moved into Privet 
Drive 
> from wherever "home" was - possibly after getting married when 
> perhaps Dudley was on the way.  
>snip
 Perhaps because I'm surrounded by 
> Hollows and Nethers and Bottoms (village names I mean!) here in 
> deepest Somerset.

Potioncat:
....Then, a good 15 years later, Mark Evans saunters into their 
lives.  It may be Petunia who gets the nasty surprise, though it 
would be hard to imagine, as nosey as she is, that she didn't know 
about an Evans family nearby!

I snipped as much as I could, but I couldn't snip the line that gave 
me the best laugh I've  had all week!

Potioncat: who doesn't live that far from Foggy Bottom.