Angelica Hale, Kechi and Mandy Harvey Shine in 'America's Got Talent' Semifinal

Kechi, America's Got Talent
 Trae Patton/NBC

Kechi performs on America's Got Talent.

Season 12's semifinal round of America's Got Talent closed the curtain on Tuesday night (Sept. 12) with six live singing performances, a mind reader, three dances and, yes, a performance by dogs. 

When it came to singing, deaf singer-songwriter Mandy Harvey stole the show with an original song, "Release Me." Harvey lost her hearing 10 years ago because of a connective tissue disorder, and her dedication to pursuing music anyway has inspired AGT judges and audiences since her audition of another original song, "Try," on June 6 (which earned her judge Simon Cowell's Golden Buzzer and a tweet from Lady Gaga).

Harvey has been associated with her ukulele, but on Tuesday night, she signed her lyrics as she sang.

And as Kechi, a plane crash survivor, sang a cover of Frances' "Don't Worry About Me," judge Mel B. wiped tears from her cheeks. The intro of the song relays a relevant message of resilience: "Even if I fall down when you're not around/ Don't worry about me, don't worry about me." 

The younger contestants, nine-year-old Celine Tam and 10-year-old Angelica Hale, also each wowed. Tam sang "How Far I'll Go" from Moana, and Hale belted out Usher's vocal from David Guetta's "Without You." Watch the (grown-up) performances below.