Imaginary Friend

Jacob announced he has a new invisible friend. Here was the conversation:

J: I have an invisible friend.
Me: You do!
J: Yes. He's a new friend today.
Me: Where is he?
J: You can't see him. He's invisible. Only I can see him.
Me: Is he here now?
J: No. He's still on the airplane. He's coming from California. He won't be here until later.