It would be annoying for sure if his father wasn't Adrie VdP and his grandfather Raymond Poulidor. I think "us" is perfectly fine here.Good thing if he doesn't move away, but I find parents who talk like that about their children annoying, famous or not. (Okay, I admit, I even sometimes do that myself. Well, I'm annoyed with my habit.)
Adrie's full name is Adrianus Aloysius Jacobus -- very cool. Also, he and Mathieu look exactly the same as very young men, although Mathieu has a bit of Poulidor's mouth.
I'm basically fascinated by MVdP. I can't imagine what it's like to have those guys as your forefathers, and then to be just as good or even better in the same discipline. I'd like to know what goes on in his head, although he seems like a pretty stoic guy. No Dumoulin, that's for sure.