Olina has her sights set on the $100,000 prize money, which she explains would help her family financially after her mother left.
"My mum left when I was around 9, and that was a hard time. There are no answers. She just left."
Olina now relies on her father, and aunt Helen.
"It was financially tough for my dad. We moved in with my aunty."
Olina continued: "My aunty Helen she was the next person I turned to if I needed anything. She was always there and I depended on her with everything I did."
"You're a star," her aunt Helen tells her.
"Winning AGT would change my family's life. It would help my dad a lot. It would give me a good opportunity to give back to my family," Olina explains.
Taking to the stage, judge Nicole Scherzinger asks Olina what she will be singing.
"'Never Enough' by 'The Greatest Showman,'" Olina reveals, which sets the audience into applause.
Olina sings her heart out and nails the song, bringing out an emotional response from Ricki-Lee especially.
"You're so amazing, you remind me of me when I was 18 I did this I auditioned," Ricki tells her when she joins the 15-year-old on the stage.
"I stood on a stage like this but it was nothing like what you just did and I just..." Ricki explains, running over to hit the Golden Buzzer for Olina!
We will definitely be seeing more of Olina Loau!
Watch more of 'Australia's Got Talent' on Channel Seven.
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