As an actor he was one of the first of the adults on Potter to treat me like a peer rather than a child. Working with him at such a formative age was incredibly important and I will carry the lessons he taught me for the rest of my life and career.
I don't spend a lot of time with kids and I don't claim to be particularly good at it, but one thing I do remember from being teenish was the growing realization that most adults talked down to me. And, sure, at 14 I wasn't an adult, but I was adult enough to know when people were talking to me like they thought I was an idiot. Maybe I was an idiot! But still smart enough to recognize the condescension.
Anyway, I try not to talk down to kids. I probably fail. Still I recommend doing your best not to.