IS Lucy O’Byrne the kind of girl who “climbs a tree and scrapes her knee”? seems an appropriate opening question for the classical singer and latest Sound of Music tour star, who found fame on BBC’s The Voice by finishing runner-up last year.

“At the moment I’ve been encouraged not to climb any trees because this schedule is quite gruelling and the producers need me in top form all the time,” replies the seemingly unflappable 23-year-old, who was selected for this month’s tour to Sunderland by well-known theatre impresario Bill Kenwright.

“I was absolutely petrified when the offer came along last year,” she says. “Delighted to be offered the chance and it was all a kind of whirlwind because I was asked to audition straight after The Voice finished. The audition process was actually quite long and I thought that I hadn’t got the part because the decision seemed to be taking so long. I thought, ‘That’s it, I’ve tried it’. When I eventually got the call I cried because I was so happy. It’s scary to think that I’m stepping into the shoes of people like Julie Andrews. It’s such a wonderful part that you have to put all that aside just to learn it because of the sheer volume of what you have to take on. Once you get it into your head, you find ways to make the role your own. It’s so easy to fall in love with the music and the story.”

She’s aware of the responsibility of playing Maria, the true story of a postulate nun who finds herself forced to flee Austria with her new husband Captain Von Trapp (played by Coronation Street’s Andrew Lancel) and his seven children at the outbreak of the Second World War. Rodgers and Hammerstein created the 1959 musical which has become one of the world’s most favourite musicals on stage and screen.

“It’s a big part of people’s lives. I met a lady at the stage door the other night and she told me that the only movie she ever went to the cinema to see with her mother was The Sound of Music, 51 years ago. It was a memory she’d kept her whole life and she had The Sound of Music wedding procession music at her own wedding. So, I realise it’s a huge responsibility to go out on stage and perform in this musical because the audience have this idea of what they want it to be. At the same time, you also know that the audience is on your side because they love it so much and care about it so much. You can feel the warmth and feel how important the story is to them. It’s nice, it’s a lovely feeling,” O’Byrne says.

The performer with a strong Irish brogue, in spite of being London-based, laughs about finding the right accent to play Maria. “The world isn’t quite ready for a Dublin Maria yet, I don’t think. I’m using an RP accent and so is my captain, who is from Liverpool. At times it’s been difficult. There are words here and there that took time to get my tongue around. I grew up in Ireland and lived there until I was 22, but I’ve watched English TV and movies all my life and the Julie Andrews accent is in your ears,” she says.

She reveals that her family (of four) were always known as “The Von Trapps” because they performed together. “Long before this was ever on the table, we were known as the Von Trapp Family because we all sing and we sing together. Although there are only four of us, we make enough noise as nine,” O’Byrne jokes.

The singer’s mother, aunties and grandmother went to see the show in Birmingham and family members also attended her debut performances in Manchester at Christmas. O’Byrne hopes they manage to catch up with her again on tour, but confesses that she hasn’t been to any of the tour venue towns and cities previously.

“The only place I’d been before was Manchester because that was where we filmed The Voice. So, apart from playing this incredible part I get to see the UK which is amazing for me. I would never have had the chance without this. When I moved to London, I worked there and tried to succeed there and it’s a hard place to get out of,” she says.

Her mentor on The Voice, Will.i.am, has Tweeted his congratulations about The Sound of Music success and her current mentor Bill Kenwright is described as “a lovely, lovely man”.

“He was at the show recently and is a very caring man. He cares deeply about this show and really loves it. When he comes into a rehearsal room, he gives everyone a hug and he makes you feel comfortable. It’s quite easy to be pretty scared when the biggest theatre producer in the UK and employee of actors comes into the room. Bill has offered my lots of advice and the biggest thing has been to trust myself and trust the material and show. It’s easy to forget that. He’s said, ‘Trust what it is and do it that way, because it’s the right way’.”

O’Byrne has no plans to slow down once she’s climbed every mountain as a musical star. “I much prefer to be working and, as a ginger, I don’t do very well in the sun. So, I’m quite happy to be in the theatre rather than on holiday. I’m always looking for the next thing, but it’s hard to think beyond being in this show until October/November. On my days off I’m still recording and promoting my album, Debut,” she says.

n The Sound of Music, Sunderland Empire, June 21 to 25. Box Office: 0844-871-3022 or ATGtickets.com/Sunderland