The Blue Eyed Bunch

Reagan went in for his kindergarten assessment today with his teacher.  He begins class next week.  As Brian and Reagan were driving home, Brian said to Reagan,  "She thinks you are pretty smart.  Where did you get your smarts?"
Reagan thought and said, "Sometimes Brad and Aubryn tell me stuff. [pause] Well, one time you did teach me something.  You told me that sweat comes out of little tiny holes on your head."