Congratulations!
He could have saved the congratulations for the car, but where’s the fun in that? Picking up someone at the airport is a great responsibility, and with great responsibility comes great power (yes, we know it’s the other way around).
We get the feeling this is a joke, and it’s a pretty good one, provided that his mother (or is it father?) has a good sense of humor. I’m sure this sign turned a few heads at the terminal, especially after his mom finally showed up.