Remus & Sirius - How DD knew

[Susan]

No: HPFGUIDX 97444

bboy_mn:
>If there are matching historical portraits at both Hogwarts and
Potters then the person in the portrait could come to his/her own
portrait at Hogwarts, and from there move through the other portraits
until he/she made their way to Dumbledore's office.
 

I don't think we have to limit ourselves to portraits.  What I've 
been thinking about is the mirror Sirius gave to Harry.  Perhaps 
everyone in the Order had an item like this.  Sirius told Harry that 
all he had to do was speak his name into the mirror.  And if it works 
anything like say the floo network, where a person can see into the 
other room (wasn't it Bagman who was even able to eat some of Molly's 
toast, even though he was at a different location?) and obviously 
hear the other person speaking, then maybe all Lily or James would 
have had to do was speak DD's name into the mirror right as 
everything's about to happen, then DD could have heard the entire 
attack, or at least been aware of the sitch.  (Though this thought is 
obviously quite morbid and definitely has holes in it.)  

And the thing about the mirrors, it seems, is that they connect 
specific people.  The way I understand it, James and Sirius could 
talk to each other when they were in separate detentions, but if Remus
had one of those mirrors as well, perhaps enchanted at the same time, 
I think they'd sort of be on the same network, so to speak, so he 
would have been able to hear James and Sirius talking as well, sort 
of like three-way-calling.  Maybe all James or Lily had to do was 
speak anyone's name into the mirror (from the Order, I mean, saying 
they all had these mirrors to connect them) then any one of them 
could have notified DD.
 
Susan,(huge Sirius fan) very much a n00b, though trying to get it 
together!