"It was actually magic. One of my favorite ever acts," Cowell tells the troupe backstage.
Ridley pursued her dreams of singing late in life, competing on season 5 of AGT in 2010 at age 58.
The 55-year-old fan-favorite singer is one of six contestants moving forward to next week's finals.
“You’re 10 years old, but you have the talent of someone who’s been performing for decades,” Howie Mandel told the young singer.
"Dee Dee, I think you’ve got a real shot at winning this competition," Simon Cowell told the Oakland nurse.
"This is what this show is all about—finding acts like this that are truly world-class," Simon Cowell said.
“You are somebody who has a God-given talent. And it’s rare," Simon Cowell told the young star.
His performance was more than just a song—it was a tribute to his wife and the journey they’ve shared.
"That stage is where dreams come true. Do you believe in dreams?"
Country singer-songwriter Roberts impressed the judges by performing her original song "Raised Right."
