Nightbirde surprised "America's Got Talent" during its recent episode with her surprise comeback.

On Wednesday, Nightbirde - whose real name is Jane Marczewski - appeared virtually in front of Terry Crews, Howie Mandel, Heidi Klum, Sofia Vergara, and Cowell. She should have been competing this week, but her health prevented her from doing so.

Showing her newly shaved head, Nightbirde sent Cowell to tears.

According to the entertainment mogul, he spoke with the aspiring singer multiple times since she revealed her worsening diagnosis on August 2.

"You made a decision, and rightly so, that your health is a priority. You said you actually felt like you let people down. You haven't let people down. Even though you haven't competed, you've already won," Cowell said as he tried to control his tears.

He sent her all their prayers and extended his gratitude for auditioning despite her health condition. For the last time, she thanked her for sharing the audition song that scored her the golden buzzer from the judge.

For what it's worth, she sang her original song "It's OK" during the audition. The piece shared the story of the last year of her life while battling cancer.

Nightbirde Thankful For The Opportunity

In response to Cowell's heartfelt message, the female singer thanked them for allowing her to tell her life story.

"We all hurt, we all suffer, and we all have the potential to overcome. It is the most beautiful thing that has ever happened to me," she went on.

Even Mendel left words of encouragement and told her that she became the beauty and fight amid the world's adversity.

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Cowell, who still tried hard to fight back his tears, gave her a wink before she signed off.

Her return came after the 30-year-old singer revealed on her Instagram account that her health took a "turn for the worse." She added that her current cancer battle now requires all her energy and attention.

During her audition, the Ohio native revealed that she has cancer in her lungs, spine, and liver. She also disclosed how she only has a two percent chance of survival.

Following her departure, "America's Got Talent" opened a Wildcard wherein viewers can vote one act out of five that can fill her space. The choices include Dylan Zangwill, Mike Goodwin, Patrick Kun, Matt Mauser, and Storm Large.

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