Car Ride

I met Cullen and Brent yesterdy after work at Home Depot. Cullen rode with me on the way home. This is what we talked about:

Cullen: "My gatorade. I get it."
Me: "Do you have it?"
Cullen: "Yes."
Me: "Good Job."
Cullen: "My special rocks, please."
Me: "Here you go."
Cullen:"Open them."
Me: "Give them to me."
Cullen:"Mommy, open my special rocks."
Me: "Here you go."
Cullen: "I drop my special rock. Get it."
Me: "I can't reach the rock, sweety. You will have to wait."
Cullen: "I know Mama. You are driving in traffic."

Where did that come from?