"Bob"

For some unknown reason, everything unknown to my son is Bob.

Mom, what's his name?
I don't know.
Is it Bob?
Sure.

Mom, who lives there?
I don't know.
Is it Bob?
Sure.

Mom, who is making that noise (someone was operating a power saw)
Our neighbours
What are their names?
Well one of them is named Cody
Who else?
I don't know.
Bob?
Sure.

Mom, who sings this song?
I don't know
Bob?
Sure

Mom, what's this song?
I don't know.
Is it the Bob Song?
Sure.

Mom, who are those kids across the street? (3 boys and one girl are playing)
I don't know
Are they Bob, Bob, Bob and Bob?
No, I think the girl is Bobette.

What's funny is Bill's Dad is named Bob, and we call him Grandpa Bob, and it makes me wonder if that ties into it somehow.