My understanding is that JKR consults on the movies, and particularly, has given the actors some specific directions about their characters.

See, I hadn't realized that—this is what happens when you have an author who's around for the filmmaking. Neat! Now I'm curious if character work from the movies ever goes the other way, into the text . . .

I'm adding this post to my memories, if I may

I'm honored. Glad it made sense to someone other than the four-in-the-morning inside of my brain.