Neve Campbell admits she was relieved not to have her kids with her when she was filming “Clouds.”

“I’d have some stuff to shed every evening,” she tells Variety. “There were days of heavy crying, and I’d just be drained.”

The Disney Plus drama is based on Laura Sobiech’s memoir “Fly a Little Higher: How God Answered a Mom’s Small Prayer in a Big Way,” about her son Zach’s battle with bone cancer. Before Zach’s death at 18, a video of him performing his song “Clouds” went viral. “We had a director’s chair with Zach’s name on it,” says Campbell, who plays Laura. “It was always on set.”

Did you know about Zach’s story before signing on for the movie?

I didn’t. I was sent the script, and when I read it, it moved me so much. I was like, who is this kid? So I went down a rabbit hole of Zach Sobiech on the internet and started listening to his music and watching Justin [Baldoni’s] documentary about him. I really wanted to be a part of [“Clouds”], but my team wasn’t sure. I don’t think it was because of the script, but teams are always apprehensive if there isn’t a big name attached to it. I remember saying, “This is about something, and that something is very important. It’s about a kid who in the face of adversity, decided to live, decided to enjoy his life and create music as a way to say goodbye to the people he loved.”

When did you meet Laura and the rest of Zach’s family?

I met them before we started filming. I finished Laura’s book the night before I was supposed to go meet her. I was so concerned that I would meet her and just start crying, which actually she would have been totally cool with because she’s just so open about her story and she understands how it affects people. We met for coffee, and we talked about being moms. We talked about her loss. We talked about her other kids and how it was for them. We hit it off, and we went deep real fast. I would call her the night before certain scenes and ask her about the experience and what that was like for her. I took some of her dialogue from the book and put it in the script because I had only recently read it so it was fresh in my mind.

What was the hardest scene for you to shoot?

When I’m telling my youngest daughter [played by Summer H. Howell] that she has to go say goodbye to her brother. That was heart-wrenching mainly because Laura is such a courageous woman and so unselfish. She would tell me, “I didn’t want Zach to be low,” or “I didn’t want the kids to be thinking about it all the time.” It’s like, how do you as a parent just not be bawling your eyes out all the time? But she would bolster herself up in order to carry this family.

There’s also the scene when you ask Zach [Fin Argus] where he would prefer to die and if he wanted to be an organ donor.

You know, it’s all real. It’s all in her book. Yes, it’s very sad and hard to watch, but there are also a lot of happy moments and a lot of funny moments. I think it’s also a timely movie when so many of us are living in fear and anxiety and panic mode. It reminds us to just be present, to choose joy and don’t sort of go down that dark hole of what-ifs. It’s a really good reminder for all of us.

For more on Zach and the Zach Sobiech Osteosarcoma Fund, go to childrenscancer.org/zach/.

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