Katy Perry cries after watching 'Idol' contestant sing with her egg donor mom

American Idol has also been a family-oriented show, and this Sunday, it showcased a special, different sort of American family story -- when 19-year-old Elizabeth Gaba showed up for her audition with both her mother and her biological egg donor. Elizabeth’s rendition of Adele’s “All I Ask” was technically impressive; like all Adele songs, it is not easy to sing, and she pulled it off. But it was a very theater-schooled performance, and judge Luke Bryan told her, “You have a very pretty, polished voice. Don’t ever be afraid to throw in a little grit.” The real emotional impact came when the judges, upon hearing Gaba’s unique family background, invited her “two mamas” into the audition room. Elizabeth, who goes by the simple stage name Gaba, was conceived by anonymous egg donation, and she recently found the donor, a woman named Amy, who she now considers to be one of her closest friends. And it turned out Gaba has inherited Amy’s talent: She’s a member of the same USC a cappella group, the SoCal VoCals, that Amy sang with years ago. (As it turns out, Amy donated her egg in order to pay for college, which is a lot more than unenthusiastic USC student Olivia Jade was willing to do.) Amy joined Gaba for an audition-room duet on a second song, and their lilting voices were astonishingly similar, proving that music is indeed in Gaba’s genes. The moment was so magical that a crying Katy Perry -- who told the three women, “Your story is a miracle” -- attempted to call her own mom. Sadly, her mother’s voicemail box was full. But thankfully, so were everyone’s hearts. Don't forget to check out Yahoo Play - our new interactive app where you can cash in your points and get tons of cool stuff! Download it now in the app store. Read more from Yahoo Entertainment:

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