Toothpick and un-invitation to Privet Drive

[occam6363]

No: HPFGUIDX 77224

I'm re-reading CoS. Harry gets a toothpick for Xmas from the 
Dursley's with a note asking him to see if he can stay at Hogwarts 
for the summer holidays, too. I'm at work so I don't have a page 
reference, but if you're browsing the book this is the time when the 
Polyjuice Potion is about ready and the Trio and Malfoy stay at 
Hogwarts for Christmas.

What the h*** is Petunia thinking? Is this a FLINT? Since OoP we know 
that Petunia knows Harry has to come home to keep LV off his back, 
and we also know that Petunia has completely (if grudingly) accepted 
this burden. Are we to assume she had nothing to do with the note, 
that it was from Vernon Dursley and not "the Dursleys?"

-- Occam