Jokes told to me by the new neighbor boy today

He is 5 years old. He was trying to make Viola laugh.

Knock, knock.
Who's there?
Hammer.
Hammer who? (At this point I was hoping for an MC Hammer reference, but the joke took an unexpected turn)
Hammer about to hit me over the head.

Viola actually was laughing, but I think it was a tragic laughter.

Knock, knock.
Who's there?
Car.
Car who?
Car about to run me over.

Is he just making these up as he goes along, and, if so, does he realize how loaded they are? The last one was best:

Knock, knock.
Who's there?
House.
House who?
House about to let me jump off the roof.

I resisted telling him the knock knock joke I made up as a kid, which I thought was totally hilarious.

Knock, knock.
Who's there?
Kenny.
Kenny who?
Kenny Rogers.

It's not nearly as nuanced as his.