In the new movie, Grint plays a teen caught between his over-bearing mother (Laura Linney) and the eccentric former actress (Walters) for whom he works.
"It was good to work with Julie again," Grint said Tuesday. "It was good having someone I sort of knew because I was a bit nervous about coming in to a new filming environment because I'm used to the 'Harry Potter' way of doing things."
"Driving Lessons" writer/director Jeremy Brock told UPI he never worried about the actors' previous roles affecting their performances -- or audiences' reactions to them.
"It was never a big issue," Brock said. "The emotional register they're playing is so much broader. (Rupert) has to do so much subtle conveying of emotion. He plays a kid who cannot express himself because he's brought up in a room-full of conditional love ... That's totally different from Ron (Weasley.)"
Celebrity Families of 2014 [PHOTOS]