Is it certain that R.A.B. is Regulas Black?

Question:

Is it certain that R.A.B. is Regulas Black?

Best Answer - Chosen by Asker: as others have said, its not "certain," but all evidence seems to point in the same direction.

for example, JK has confirmed that we are not meeting any new characters in book 7. Also, the Dutch version of HBP has the initials RAZ, but "Black" is "Zwartz" in dutch, so it translates to the same conclusion. Finally, many members of the Black family have names representative of stars, (ie- Sirius- the dog star, Bellatrix- the female warrior, ect). Regulus is the "heart" of the constellation Leo- aka- the heart of the lion. He was a Slytherin with a Gryffindor's heart, waiting for that can-do moment to be brave.