Elephant & Piggie: Let's Go For a Drive by Mo Willems
Gerald is careful. Piggie is not.
Piggie cannot help smiling. Gerald can.
Gerald worries so that Piggie does not have to.
Gerald and Piggie are best friends.
In Let's Go for a Drive! Gerald and Piggie want to hit the road! But the best-laid plans of pigs and elephants often go awry.