Naomi Watts talks "The Book of Henry," fear of singing

Naomi Watts, Jaeden Lieberher and Jacob Tremblay in "The Book of Henry."

Alison Cohen Rosa / Focus Featur

Naomi Watts may be the mother of two sons in reality, but she says her latest role is nothing like her own parenting experiences.

Watts stars in the new drama "The Book of Henry" as a struggling single mother to two boys. Her younger son (Jacob Tremblay) is a playful 8-year-old, while her older son (Jaeden Lieberher) is a precocious genius who keeps the family in line while helping his mother and brother navigate life.

It's the latest film from filmmaker Colin Trevorrow, who most recently directed "Jurassic World" and is set to direct the upcoming "Star Wars: Episode IX" in 2019.

Watts has previously starred with both Lieberher (in "St. Vincent") and Tremblay (in "Shut In"), but she says this time around she found herself even more surprised by the two young performers. She spoke with CBS News ahead of the film's premiere at the Los Angeles Film Festival.

What makes the relationship between this particular mother and her sons ideal for this story?

I don't know, she's a different kind of mother. She's not grown up and in many ways is letting her eldest son take care of things. He really shouldn't be doing what he does -- like pay bills and manage money -- but he's just really a special kid and has all these incredible gifts, and she kind of let's it happen because it's always worked. So she's never really questioned it. She's someone that encourages the fun and the high-spirited creativity in both of them. And I just loved her. I love playing her. They go through a lot together, and it's a beautiful connection she has with them for me, too.

Your character spends much of her life learning from her kids. Did you relate at all to her in this way?

Yeah. I mean, hopefully not as much. I mean with my kids, I don't want them to be responsible for doing any of the parenting. It's amazing, though. You watch these kids and they teach you so much -- not just my own kids, these kids in the film. They just always surprise you with the things they come out with.

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Naomi Watts, Jaeden Lieberher and Jacob Tremblay in "The Book of Henry."

Alison Cohen Rosa / Focus Featur

I've heard that acting with kids is a completely different experience.

You never know what you're going to get. I feel like today I get lucky and work with some really amazing actors, really gifted child actors out there. I've worked with both of these guys before, so I already knew that about them. In these roles, though, I got to work more closely with them. And yeah, I was super-impressed.

You also had your first singing experience in this film. How did you prepare for that?

You are the first person that's asked me that! I was terrified. I'm not a singer, and I've always been frightened. In fact, I've got memories of when I was a child singing on stage and my own family was teasing me, saying, "Oh my gosh, don't ever sing again!" So it's like old wounds. So then when I finally got to do this I was really scared and I had to play the ukulele, which I really played in the film and learned in two weeks. So yeah, it was fun. It was as scary as anything.

"The Book of Henry" is in select theaters Friday. 

THE BOOK OF HENRY - Official Trailer [HD] - In Theaters June 16 by Focus Features on YouTube