Milo Manheim says it makes so much "sense” that Ariana Grande and Liz Gillies are such good friends after recently getting to know both performers.

Manheim, who stars alongside Gillies in the off-Broadway production of Little Shop of Horrors, spoke to PEOPLE exclusively at the Disney 2025 Upfronts in New York City. During the conversation, the actor explained that he met Grande when she came to the show in order to support Gillies, whom she’s been close to for years.

“They're both such sweeties,” Manheim, 24, said. “I mean, I've spent so much time with Liz and she's like family now at this point. We've been through so much together. I've learned so much from her, and the more I get to know her, the more incredible I think she is.”

“Ariana came to see the show,” he added, noting, “It makes such sense that they are friends. They're both such kind souls, both such theater girlies. Like it was, it was really nice to see Ariana there supporting Liz, and I could see them just being like little girls again enjoying being in the theater.”

Gillies, 31, posted photos from Grande's April 26 visit to the show, jokingly captioning the post, "THANK YOU FOR COMING TO THE SHOP, MY DINGUS!! 😭♥️🪴."

Grande, 31, attended Little Shop of Horrors with boyfriend Ethan Slater, and a source told PEOPLE that they arrived about an hour early “and hung out backstage with the cast.”

The source went on to describe the visit as “adorable,” adding, “They were both so friendly and warm with the cast, and so supportive of the production. Ariana gave everyone hugs and brought Liz a potted plant for the women’s dressing room.”

Grande and Gillie met as children starring in the Broadway production of 13. The pair were later cast on the popular Nickelodeon series Victorious, which ran from 2010 to 2013. 

The show, which followed a group of teens who attend a high school for the performing arts, was Grande’s first television role and served as the launching pad for her music career.

The pair continued to remain close over the years, with Grande tapping the Sex&Drugs&Rock&Roll alum to appear in her "Thank U, Next" video in 2019.

"We're totally close. She's like blood to me, she's like my sister," Gillies previously told PEOPLE of the in 2015. "So unless we have a massive falling out, nothing will be happening there. We lived together, I've known her since what feels like the beginning of time."

Grande shared a heartfelt birthday tribute to Gillies on her Instagram Stories for her 30th birthday in 2023, writing, “Happy birthday to the most beautiful, brilliant, talented, funniest person I've ever met in my life @lizgillz," over a candid selfie of the pair.

Little Shop of Horrors is playing at the Westside Theatre in N.Y.C.