Lenghty post ahead!

When it comes to Rey I see it as such that he is either...

A. Rau's clone. This would explain the reaction he has with Neo (read: Mwu) as well as similarities and whatnot.
B. Rau's son. Again, similarities and newtype reactions.

Personally I'm quite sure that it's A, for another reason as well.
Remember the flashback where a little Rey runs around with both of his "fathers"? He's just a little kid there, yet Gil & Rau don't look much younger than they did later on.
This leads me to believe that perhaps Rey has grown up faster than he should have, which means that he's inherited Rau's "rapid aging" genes.
That is the main reason to why I believe he's a clone, because being one he'd naturally have the rapid aging as well.

Does this sound sane?
As for his reaction to the lab, it is possible that he was "created" there?

Totally crazy theory: Remember Auel's "mother"? She did look a lot like Rey right? Imagine that Rau was there and knocked up the nurse, creating little Rey who then grew up at the lab? [img]i/expressions/face-icon-small-tongue.gif[/img]

Can't wait to find out about all this. I'm desperately hoping that Rey is more than just another clone though. I'm quite tired of clones at this point...

What we can say for sure though is that Rey loves Rau & Gil, seeing as he follows Gil's orders and treats him like a father. Also, the flashback of Rey's when Providence blew up indicates that Rau's death meant a lot to Rey.

But why would Rau clone himself?
Again, I have two theories:

A. He knew that his time was short, what's with the aging and whatnot. Thus, he wanted to "recreate" himself.
B. He wanted a "heir" to his ambition of destroying mankind.

B is more likely in this case. Quite possibly Gil eventually came to share Rau's views on mankind, and is behind the scenes trying to achieve what Rau aspired to towards the end of Seed. But still, I am sure that there is much more to it than this... and again, CAN'T WAIT!

Finally, Rey rules. Such an intriguating character.