OoP: Petunia, expelled?

[fro6662002]

No: HPFGUIDX 64824

I'm not so sure about the 'expelled' theory. I tend to lean towards 
the idea that she was indeed at Hogwarts at some point, but that it 
was a world which she hated and wanted out of. Furthermore, I think 
that this idea resolves the issue of the 'pact' between Dumbledore 
and Petunia, insofar as 'What was in it for Petunia?'. My idea on 
that being that Dudley was also born destined for the Wizarding 
World, the world which Petunia despised. I feel that Petunia's side 
of the deal was that in exchange for taking in Harry, Dumbledore had 
to guarantee that Dudley, though destined, would never enter that 
World.

I also think that Petunia has some residual magical powers. Hear me 
out. OotP (The Advance Guard) Tonks comments twice on the 'unnatural' 
cleanliness of Petunia's house. In itself, a fairly, innocuous 
remark. However the repetion seems to be drawing the reader's 
attention to this. More importantly is the repeated use throughout 
the book of the spell 'Scourgify'(cleaning spell) as though JK wishes 
to draw the reader's attention to that also. Scourgify, I would 
anticipate is an elementary level spell along the lines of Alohamora 
or Wingardium Leviosa, which if so would have been learnt in years 1 
or 2. Does Petunia use 'Scourgify'?

One further point is the girl laughing at the scrawny boy trying to 
mount a bucking broomstick (Seen and Unforeseen - Harry's Occlumented 
vision of Snape's childhood). Who is the girl? I'm taking this to be 
Lily, as Harry's visions of Lily seem also to feature Snape. Is this 
Lily playing with Snape as a young child? Did Petunia also play with 
Snape as a young child?