Never-Ending.

Conversations at the doctor's office.

Dr. S.: "Corbin, what does it mean when someone says that it's raining cats and dogs outside?"
Corbin: "I don't know."
Dr. S.: "Well what do you do when someone says that?"
Corbin: "I look out the window."

and then...

Dr. S.: "Corbin, I'm going to tell you a joke, okay?  How do you catch a squirrel?"
Corbin: "Umm...with a gun?"
Dr. S.: "Nope, you climb a tree and act like a nut!"
Corbin: (pause) "Ha ha ha" (fake laughter)
Dr. S.: "Did you get it?"
Corbin: "No."
Dr. S.: "Because squirrels like to eat nuts but people can also act nuts."
Corbin: "Ohhh.  Okay." (still not really getting it)

 Mixed with stories of him loving Pokemon but only so he can collect, sort, and line them up in a perfect array on the floor rather than play a game.  Loving legos but never building anything only sorting them.  Mixed with only wanting to read books that list facts, rather than tell a story.  Mixed with having language-processing issues yet a whiz at math and science.  Mixed with getting along with everyone but not really having any close friends yet.  And tons of little itty things....

Gets you a referral to see if your child may have Aspergers syndrome.