Those are the names of Jack's former "imaginary friends" from about a year and a half ago. I pretty much thought they had disappeared. But, while watching an episode of "Charile and Lola" this afternoon (the cutest cartoon out there in my opinion) we were reminded of imaginary friends when Lola started speaking to her friend "Soren Lorensen".
me: Jack, how are Vook and Mo doing? (I wondered if he would even still care?)
Jack: Fine (eyes not moving off the TV screen)
me: But can you still talk to them? Or do you?
me: How do you get them to come out and talk to you again? (I just want to see him do it)
Jack: (still only looking at the TV, he claps his hands once and then holds them out for me to inspect) They're right there.
me: Oh, and so they are.
Jack: Can I put them back please, I'm trying to watch this. (point point)