Unlike some couples, Avengers actress Elizabeth Olsen and her musician husband Robbie Arnett don’t shy away from working together.

Their new children’s book, Hattie Harmony: Opening Night (following their first best-seller Hattie Harmony: Worry Detective) offers young readers tools to manage anxiety such as journaling, time-outs and self-reflection. Both books are illustrated by Marissa Valdez.

“It’s so funny because I had this instinct where I was like, ‘Oh, I don’t know, how are we going to do this?’ But honestly, our whole relationship is built on communication,” Olsen, 34, tells PEOPLE in this week’s issue. “Obviously you’d hope that most relationships are, but it’s very easy and enjoyable for us to problem solve.”

When they aren’t working, a perfect day off for the couple entails the simple things. “Coffee, walking in the garden, journaling and then gardening,” says Olsen. “And going to the grocery store and figuring out what to make for an early dinner. Reading in the afternoon, making a cocktail and cooking. That’s my favorite, favorite day.”

For Arnett, 31, it’s “coffee, and then I’ll go write. And then hopefully we’ll watch a really great movie,” he says. “And then [go to] bed early and do it again. Real exciting stuff.”

Married for three years, the two have found a rhythm in their life. “We can talk about anything, and it’s very, very comforting to kind of tackle anything together,” says Arnett.

Olsen insists she’s “most grateful for his humor. He makes me laugh every day, easily before noon.”

“Yeah, that was my goal setting out, to figure out how to make her laugh once a day,” adds Arnett. “And I haven’t had to do it intentionally. I can’t tell if that’s a bad thing or a good thing.”

Hattie Harmony: Opening Night is on bookshelves now.