Family members but not walt?

[admire]

Hey Jack

I think that last weeks crackpot theory was really cool but if you are right, then why would Walt be alive? Or his grandmother? Walt knows about a lot of stuff.

[Jack]

Only a few people know Walt is alive. Most people think he died in the plane crash.

He's Walt Johnson now.

My theory is they're only killing the family members of the Oceanic 6, but after last nights episode. I have no idea what's going on.