Jack's first knock knock joke.

So I am in the kitchen the other day and jack walks up to me with a big smile on his face and goes:

"Mommy knock, knock." instinctively I say. "Who's there?"
Jack: Apple
Me: Apple who?
Jack: Are you gonna let me in????

And then he busts out in this big bright laugh that lit up the whole room.

It wasn't a very funny joke. I am still kind of scratching my head on where he heard this from or what the orginal joke was and how it changed for the purpose of Jack's joke.
Still I couldn't help but laugh because of his reaction to his own joke. He was so excited to tell me a joke to make me laugh that it made him laugh. He was so excited just to see me smile that it made him smile.

Three days later I am still telling that joke and I get the biggest kick out of it. the people I tell it to probably think I'm crazy and don't appreciate it as much as I do, but it's still greatness to me.
I wish I had a video camera so I could show the whole world how cute that moment was.