At her first rehearsal with the Australian Children’s Choir, Sascha Davis knew no one and felt nervous.

It was 1987 and she was seven years old. Then she spied a smiling girl, about her age, called Kate Howard.

“She tapped the chair next to her and said come and sit next to me,” Davis recalls.

The girls sang together for the next decade and became lifelong friends.

“We got on like a house on fire,” Davis says. “We went to different schools and it was only the choir we had in common, but we’re still as close today as we were back then. It’s pretty remarkable.”

Since its founding in 1976, the Australian Children’s Choir has toured the world, most recently performing in St Peter’s Basilica in the Vatican.

Davis and Howard are among 90 ex-choristers who will perform in an alumni choir, on a bill with the current choir, at a concert to celebrate the choir’s 50th anniversary.

Davis says being in the choir, until 1997 at age 17, was “mind blowing”, including accompanying Marina Prior at an Australian Open tennis final and singing at a VFL grand final.

She remembers that John Farnham once came to a rehearsal and sang with choristers.

Senior Australian Children’s Choir members accompanied Farnham on the song You’re the Voice at some of his biggest concerts.

But it’s the friendship with Howard that’s been a particularly special highlight, Davis says. “We were bridesmaids at each other’s weddings and held each other’s babies,” she says.

Howard’s siblings Nicole and Olivia (Livvy), who were also choir members, are like sisters to Davis.

Kate Howard says that apart from the “awesome” friendship with Davis, the choir helped shape who she is, instilling discipline, confidence, and reliability.

It’s been a joy to rehearse for the alumni choir and reunite with old friends, she says.

Alumnus Jake Hoskin met his now-wife, Marie, when they were teenagers in the choir 25 years ago.

One of their biggest gigs was performing, complete with face paint, the song Great Expectations with rock band Kiss at what is now Marvel Stadium.

In free time on a choir tour of Austria, Jake and Marie re-enacted the I Am 16 Going on 17 scene from The Sound of Music in a gazebo near Salzburg, giggling because Jake was the Liesl character’s age of 16 and Marie was 17 going on 18, like Rolf.

Today, the Hoskins’ son Owen is five years old, the minimum age for the choir’s junior section, and the couple would love him to join.

The Children’s Choir’s current artistic director, Daniel Brinsmead, said the choir had survived thanks to the dedication of the staff and choristers’ families, and to community support.

“It’s beloved, particularly within Melbourne,” he said.

The choir’s 50th anniversary concert is on September 5 at 2.30pm at the Melbourne Recital Centre’s Elisabeth Murdoch Hall.

Auditions for future choir places are available for children aged five to 16 via www.theacc.com.au