"And yet playing a mother has become this kind of fascinating talking point," she continues. "To me, a mother is human. She has her own life and it just makes it so much more complex, rich and profound to add that incredible relationship with kids. Not just mothers that I've played but with every character I've played, I try to make them really different. Other than the fact they're mothers and have really interesting relationships with their kids, I think all of them have been different. Or at least that was my attempt."
In co-directors Nat Faxon and Jim Rash's gently engaging drama, Pam's unconfident 14-year-old son Duncan not only has to deal with his shyness, he also struggles to overcome the strange, bullying behaviour of her new boyfriend, Trent, played by Steve Carell in a mildly caustic role for him. Pam fails to understand her son's problems, glossing over the real issues while attempting to forge a deeper bond with Trent. With two children herself, Sage Florence, 5, and Ario Robert, 2, Collette seems even better positioned to play mums that all mothers can relate to, even as they're being entertained by her talent for humour and observation.
"You know, it probably has helped being a mum but I don't know how, if it has directly, or even how to articulate it because every experience you have affects how you approach everything," she argues. "But I wouldn't say there's an overt difference in how I work, other than the fact that I want to spend as much time with my kids, so I want to get home really quickly at the end of the day."
Considering the Blacktown-born actress works frequently in Hollywood, London and Australia, home life must get stretched to breaking point at times. Not so, insists Collette.
"No it doesn't because we get to have so many wonderful experiences," she says. "We get to travel all around the world as a little travelling circus, experiencing different cultures and people. I think it's actually a really wonderful learning curve for my kids. I'm kind of over feeling guilty about it because the more people I speak to about it the more I realise it's an education in itself.
"More than anything, it just makes you prioritise and get your schedule together," she laughs. "And also, when I work on a movie, work can be intense and the hours are full on, but it's not like a normal job because then I can have several months off where I'm with my kids 24/7, you know."
Collette fails to see any distinction between her work in one country or another, preferring to see it as an amorphous career that isn't defined by time or place.
"Ah, well, it's really all just one career," she laughs. "In a way, I've never really had any kind of game plan. There's nothing like, 'I'm gonna do this kind of movie, I'm gonna play that kind of character'.
"I'm very much about just taking things in my stride, and certain films present themselves when they're meant to be. It's never felt like any kind of struggle or a desperate need to balance it all out or anything. Everything seems to work pretty effortlessly, experience after experience."
With so many quality films and well-deserved awards to her credit, not to mention the slew of great mother roles, Collette's strategy is working, even if she says it isn't really a strategy at all.
"Whatever it is, I just hope that it's fun."
The Way Way Back opens in cinemas on Thursday.
