“Might be/Maybe not”

Finn is talking up a storm, but even we struggle to understand him some of the time. This plus his increasing grasp on useful little phrases led to a funny exchange the other day:

“Boo* book,” he said–possibly gesturing at a coloring pad–“Boo book!”
“Uh, boo book?” I asked with some hesitation.
“Uh Huuh” he chirped. But reading my hesitation, he added, “Might be.”
“Might be?,” I repeated.
“Uh huh,” he said. And then after a beat, “Maybe not…”
* Halloween has gotten him hooked on ghosts, and he loves his “Boo shirt,” saying boo (“Scare Mom-O!”), and even calling himself “BooMan.”