In Berkeley Repertory Theater’s current production of “Brundibar,” 14-year-old Lia Friedman-Salaverry has a small part as a ghost and street urchin. She has no speaking lines, no musical solos, no spotlight.

But in a sense, Lia is the star of the show.

Tony Kushner and Maurice Sendak’s “Brundibar” reworks the 1930s-era musical that ran for 55 performances in the Theresienstadt concentration camp during the war years. The original cast featured interned children.

The simple yet life-affirming musical was a tiny effort to entertain camp prisoners and subtly stick it to the Nazi tyrants. “Brundibar” composer Hans Krasa, along with the entire original cast (save two), later died at Auschwitz.

One person who surely saw one of those 55 performances was Klara Friedmann, Lia’s great-great grandmother, a Theresienstadt prisoner who later perished at Treblinka.

Now, all these years later, Klara Friedmann’s descendant has landed her first professional acting gig in the very same musical.

“It’s amazing,” says Lia about the dramatic link between her and her ancestor. “I think about it before I perform. It gives me a level of seriousness and understanding.”

Prior to “Brundibar,” Lia had acted only in school plays. She never had singing or acting lessons, but after responding to an open audition, the East Bay teen and Midrasha high-school student landed the part alongside more experienced young actors.

“I love being on stage,” she says. “I don’t feel stage fright. If the audience connects, knows the jokes and claps, it really feels great.”

In that audience for most performances has been Lia’s mother Sari Friedman. Seeing her daughter shine in this of all musicals has been an emotional experience.

“I just weep,” says Friedman. “I think about the original cast of 150 kids sent to Auschwitz. ‘Brundibar’ was an act of love for the children in Theresienstadt.”

For Friedman, there’s even more in her backstory. She grew up in New York City, the daughter of two German-born Holocaust survivors. Though both her parents escaped Europe, virtually their entire families were murdered.

“It was a constant presence in my life,” says Friedman of the Holocaust. “My parents were terrified that I would be interested in Judaism.”

For most of her life, Friedman gave her parents nothing to fear, but about 10 years ago, the teacher-novelist developed a passionate interest in both Judaism and the Holocaust, topics her taciturn parents, both traumatized by the war, could not address. “I changed my way of relating to this,” she recalls. “I read Holocaust material nonstop.”

Friedman says her folks still have a hard time dealing with the tragedy, but Lia’s participation in “Brundibar” is a testament to the possibilities of hope and healing. Today, Lia takes her Jewish faith seriously, keeps kosher and observes Shabbat.

After the Berkeley Rep run, “Brundibar” moves on to New York, Boston and Yale University. Those productions will feature different casts, but Lia is certain this is not the last production for her. She wants to keep acting, especially if future projects can be as much fun as this one.

“The whole cast is bonded,” she says. “I’ll remember the people I’ve been close to, being on stage and knowing the purpose. I’m glad I can do something for my heritage.”

“Brundibar” plays Tuesdays through Sundays, through Dec. 28 at Berkeley Repertory Theater, 2015 Addison St., Berkeley. Tickets: $15-$64. Information: (510) 647-2949 or www.berkeleyrep.org.