If it is not Voldemort, then who? - Is Dumbledore worried about someone else?

[David]

No: HPFGUIDX 153428

> David said:  Well, speaking of suspicious, I find it suspicious
> that Dumbledore had to clarify who Harry was talking about.  Who
> else did he think Harry might be talking about?  <snip>
>
> Peggy now:  I take Dumbledore's comment as his having been called
> out of deep thought and back to the present moment by Harry's
> question.  I think he was verbally giving his head a shake to get
> the various thoughts cleared out so he could continue the
> conversation with Harry.

David says:
I thought about Dumbledore just being deep in thought, but for some
reason, I don't think that's it, I think that JKR wrote it that way
for a reason.  It could be just conincidence, but is there such a
thing as "just a coincidence" in a JKR story?