The “Frozen” cast reunited for a good cause.

On Tuesday’s “Jimmy Kimmel Live!” — guest-hosted by Josh Gad — the star of the Disney animated hit brought together co-stars Kristen Bell, Idina Menzel, and Jonathan Groff to make a healthcare worker’s day.

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For this week’s “#HealthCareHero” segment, Gad virtually invited NICU nurse Kellie Mercer onto the show.

“With COVID happening, babies never stopped coming,” Merner said of working during the pandemic. “So, we remained very busy. We just had to learn to adapt, to wear more PPE, and go with how the wind changes. The biggest change has been our visitor policy. Parents are no longer allowed to visit their babies together, which is challenging because they can’t have that bonding experience together with their babies.”

She also confessed to being a massive “Frozen” fan.

“My fiancé and I—in love with ‘Frozen’,” she gushed. “We often sing ‘Love Is an Open Door’—that’s our No. 1 duet. But my stepmother is the real, true Olaf fan. She has hundreds of Olafs, including an Olaf-themed bathroom.”

In fact, Mercer revealed that she was originally intending to have a Disney princess-themed wedding in June, though it was postponed due to the pandemic.

“I got engaged at Cinderella’s Castle in Magic Kingdom,” she explained. “So, from then on, we knew that we were going to have a Disney princess-themed wedding with the princess dress, the hidden Mickeys and we of course had to tie ‘Frozen’ in. So, at our bar, our sign says ‘love is an open bar.'”

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Gad then brought his “Frozen” castmates onto the video call, rendering Mercer speechless.

The guest-host also had each actor bring something old, something new, something borrowed, or something blue onto the call as a wedding gift.

“We couldn’t find your registry and all of Arendelle’s malls are still closed,” he said, “so we made do with stuff found around the house.”

Gifts included a 1,000-piece “Golden Girls” puzzle, a stuffed Olaf doll, and Menzel’s gown from her performance during Taylor Swift’s “1989” world tour.