[meteorite-list] Vesta, for sure?

[Richard Montgomery]

Hi List...this is a completely neophyte question, so please accept my 
ignorance in things astronomic...and allow me to ask you experts:

I have always wondered why Vesta is the parent-body-de-jur for our HEDs, 
when so many unfound asteroids are no doubt cruizing around out there. 
Hence my question:  Have any asteroids been "paired" yet, and if not, why 
Vesta alone gets the credit; as well, couldn't our HED cousins be cousins 
from a yet-to-be-discovered asteroid pairing?

As you true scientists of course recognize, I'm completely green in this 
area.  I guess it's my timeless query (X-factors-we-need-to-consider) that 
has me bewildered.  Has Vesta somehow distinguished itself as the 
one-and-only parent-body?

I do understand reflection technology has identified our HED meteorites to 
be from Vesta, but why not an undiscovered twin?  Or many multiple twins?

With deference to those of you already in the know,

Richard Montgomery