Talking to the boy in the mansion can make him freeze up, meaning he doesn't walk around anymore. Can cause a problem if it happened in front of a door.
I had this problem. At once point I had to reload twice because the little shit got stuck first in the doorway of the bedroom, then in the doorway of the kitchen. It's not talking to him that does it, sometimes he just moves to an inconvenient place and stops moving. What we really need is a way to push non-hostile NPCs.
I thought it was ironically hilarious that his mother said "don't let my son get in your way, now" when she let us search the mansion, though.