'Frozen' Star Caissie Levy Shares What It Was Like for Her Son to Grow Up with Elsa as His Mom

For the vast majority of 5-year-old Izaiah's life, mommy has always been Elsa of Arendelle.

Caissie Levy, who originated the role of the snow queen in the Broadway musical Frozen, gave birth to son Izaiah in February 2016, a year and a half before the stage adaptation of the hit Disney film began its out-of-town tryout in Colorado ahead of its New York City opening.

"Izaiah has only known me as Elsa," Levy, 40, tells PEOPLE exclusively. "To be a mom for the first time and have those two things converge at the same time was just wild."

The theater has turned into Izaiah's second home. In fact, when Levy was pregnant, she starred in Off-Broadway's First Daughter Suite until she was about five-and-a-half months along — and Izaiah's first kick was felt while the Broadway actress was on stage.

"[It was] just magic and crazy and out-of-body and wild, and also felt completely right," Levy recalls. "Here I was, doing a show pregnant, and my baby was part of that."

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It's no surprise that Izaiah's artistic parents — Levy is married to actor and composer David Reiser — have rubbed off on him.

"He's very into art and drawing, and he still draws pictures of me in my costume and talks about being backstage," Levy explains, adding that Izaiah had been to the show multiple times throughout her two-year Broadway run and even got to watch from the wings as she sang the musical's iconic number "Let It Go."

"To see his face. I mean, it made me so emotional to try to sing that song when I knew he was right there watching me," she says. "How special it was that I got to perform that for him."

Levy left Frozen a month before the coronavirus pandemic swept the United States and shut down Broadway houses in March for over a year. Though her career was put on pause — she was just one day from beginning performances in her next project, the Broadway revival of Caroline, or Change — quarantine opened a new door for their family.

Levy says that she and her husband thought, "Okay, it's now or never. I'm not doing a show for the first time in a decade or something, let's try for this other baby." In March, the couple welcomed their second child, a daughter named Talulah Ruby, and have enjoyed celebrating each of her milestones for the first six months at home as they awaited Broadway's full reopening.

"We feel like she's always been here," Levy says of their new addition, adding that their quality time with Talulah has been "delicious."

This week, Levy is back to work — playing a Jewish mother in Caroline, or Change, a role she says she very much relates to — and is excited to begin performances Friday at Studio 54.

Sharing the stage with the child actors who alternate the role of her stepson has new meaning as a mother of two.

"I just keep thinking, 'Oh my gosh, these boys are somebody's baby, and they're letting their kids go on stage!' It's so wild. My heart just pounds for them because I get nervous and excited for them, and I think about how their parents must feel watching them on stage," she shares.

"The mom side of me is very protective towards all the young people in the show because I just want them to feel good and happy and enjoy themselves because I remember that they're somebody's baby. And then I think, 'Oh my gosh, is my child gonna be this age one day?' "

When her two children do grow up, Levy says she would be okay with them following in her footsteps as a performer, so long as they're happy. "I think the only thing I really hope for my kids is that they feel good about themselves, like themselves and have fun. So if that ends up leading them into somewhere in the arts — on stage, backstage, music, visual art — I'm all for it."

"I'm grateful my parents let me be who I was," she adds, "and I just want to do that for my kids."