I've just noticed something. In GoF, when the newly reborn Voldemort gathers his ols Death Eaters around him, he speaks about the six that are missing:
"And here we have six missing DEs...three dead in my service. One, too cowardly to return...he will pay. One, who I believe has left me forever...he will be killed, of course...and one, who remains my most faithful servant, and who has already reentered my service."
There been quite a few discussions in here about who's the coward and who's left forever, but now I wonder:
Rosier and Wilkes were killed by Aurors. Who's the third that died?
Most people I've talked to seemed to believe it's Regulus Black, but he was killed on LV's order, and I wouldn't call it "death in my service", or even regard it worth mentioning. And was Quirrel a Death Eater? I don't think so. So who was number three?