Girl, 4, Who's Been Battling Rare Condition Since She Was a Baby Sings 'Overcomer' From Hospital

"It's like a revolution of joy," Leah's mom said.

Lindsay Carroll says music has always been in her 4-year-old daughter, Leah.

Now the little girl, who suffers from a rare blood disease, is sharing it with the rest of the world.

A viral video shows Leah singing “Overcomer” by Christian recording artist Mandisa while in her hospital bed in Oakland, California. Her mom told that this particular song means so much to their family that when Leah started singing it, she just had to document it.

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“It really speaks to us,” Carroll said. “[It's about] just getting over anything that’s handed to you through our faith and staying strong.”

With more than 300 hospital admittances and two long stays in Oakland, Leah has shown incredible strength.

She was just 5 months old when she developed a cold that she just couldn’t shake. Then at 6 months, she developed a fever and, two days later, septic shock.

Leah was airlifted from their home town of Manteca, California, to Oakland Children’s Hospital where she was diagnosed with severe congenital neutropenia, a rare disease that causes recurrent illnesses because the body cannot make the white blood cells needed to fight off infection. According to Carroll, Leah has the “rarest form of an already rare disease.”

Leah was put on the transplant list and at 13 months old in 2014, she had her first bone marrow transplant. She was in Oakland for five months during this procedure and two years later, the family learned the donation had failed.

Last March, she received her second bone marrow transplant. Now the family is waiting to see if this donor will properly graft.

"I think any adult going through this wouldn’t have half the spirit she does, but that’s what so unique about her,” her mother said.

As they wait to see if the donor works this time around, Leah passes the time by singing her favorite songs and watching music videos on her iPad.

“It’s able to just kind of take her mind off of reality, whether she realizes it or not,” she said.

Leah’s current jams include “Bad” and “Beat It” by Michael Jackson and “Everlong” by the Foo Fighters. She also loves Adele, Megan Trainor, Taylor Swift and a song her mom wrote for her called “Leah Renee.” For her fourth birthday, Carroll bought Leah a drum set, which she loves.

“This is her life,” her mom said. “It’s what she’s ever known and she likes to be happy, she loves to perform, and she likes to make people feel good.”

Her latest video is doing just that. Carroll said she often gets 15,000 to 30,000 views on Leah’s videos, but when this one reached hundreds of thousands of views, she realized it was particularly special. Even Mandisa, the singer of “Overcomer,” shared the video of Leah belting out her song.

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Now the video on the Facebook page, Prayers and Love for Leah, has five million views and with Mandisa’s share, the total views have reached about 16 million. Carroll has received messages from people across the world, including those whose friends have gone through transplants.

And that show of support is just what is needed.

“It’s like a revolution of joy,” her mom said. “And I feel right now is the time for that.”

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