[Sistermadly]

Okay, I'll bite:

Faux!Vaughn is Russian (kinda like Sarky-poo and Spy!Mommy). His mother and father were KGB agents who went rogue and abandoned the KGB. Spy!Mommy helped them escape and in exchange for helping her with her plans for world domination, she somehow got them new identities, brought them to the States and set them up at the CIA (with Spy!Daddy).

Because Spy!Mommy has been a follower of Rambaldi, she knew about the prophecy and knew her daughter would need protection. But she also knew that parts of the Prophecy would have to be played out, otherwise Faux!Vaughn and Syd would never have met. Thus because the Faux!Vaughn family had a small child, she engineered the whole thing. Faux!Vaughn went through a similar training program that Syd went through when she was a child. Something happened and Faux!Vaughn's dad betrayed Spy!Mommy, and she had him killed. Faux!Vaughn then had a mission: to find the person who killed his father. It just so happened that his path crossed with Spy!Mommy about two years before Syd joined SD-6, and during his meetings with Spy!Mommy, she told him about the Prophecy and his role in it. So when Syd came into the CIA to spill the beans on SD-6, the fact that she met Faux!Vaughn was no coincidence: it was Spy!Mommy's doing all along. That explains why she wasn't mad that Faux!Vaughn has been deceiving Syd all this time, because it was all her doing anyhow.

How's that?