Laura Linney on 2-Year-Old Son's Penchant for Asking Everyone if They're Happy: It Can 'Take Your Breath Away'

Even though the general public never caught wind of her pregnancy, Laura Linney has a 2-year-old son named Bennett Armistead.

And the three-time Oscar- and Tony-nominated actress couldn’t be more overjoyed about motherhood — especially considering her transition back to work was relatively easy.

“Yes, I had just had the baby,” Linney told PEOPLE at the Sunday premiere of her new film Genius at New York City’s Museum of Modern Art, explaining that Bennett was with her while she worked on two recent films.

“I had done Mr. Holmes and then I did [Genius] right after that. Both movies were in London,” she says.

“But the [sizes] of those parts were perfect for someone who [had] just had a child. I was able to get my feet back into work and still have time with my infant. It was a wonderful time.”

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In Genius, Linney plays Louise, the playwright wife of Maxwell Perkins (Colin Firth), one of the greatest book editors — he edited Thomas Wolfe (the subject of Genius, played by Jude Law), F. Scott Fitzgerald, and Ernest Hemingway.

Meanwhile, little Bennett is growing faster than ever.

“He’s adorable,” Linney, 52, shares about the precocious love of her life. “It’s amazing to watch his language come together. It breaks my heart.

“He’ll go up to you and say, ‘Are you happy?’ That’s his big question,” she continues. “He asks everybody, ‘Are you happy?’ And it does sort of take your breath away.”

When told this was uniquely thoughtful for a toddler, Linney replies, “I know, adorable.”

And what does he love to play with? “Trains, trains, trains,” she answers, adding, “All of that” when asked if Bennett’s love applies specifically to Thomas the Tank Engine.

— Jeffrey Slonim