Boy with rare form of leukemia to receive life-saving bone marrow transplant from sister

TAMPA, Fla. - A Bay Area boy’s search for a matching bone marrow donor came to an end on Wednesday. 

Just over a month ago, 12-year-old Colton King was perfectly healthy and thriving on the baseball field, but now he's at St. Joseph's Children's Hospital battling an extremely rare form of leukemia. 

The family has been desperate to find a bone marrow donor for a transplant. On Wednesday, they found a match in his 16-year-old sister Kaylee.

Colton King lives for the game of baseball so for his 12th birthday the batting cages only made sense.

"He would take a swing and then just kind of need a break and kind of rest and that's very unlike him and I was like, man, this doesn't seem right. Something in my mom's gut was just like, okay, this is really wrong," his mom Stacey King said.

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At urgent care, his blood work showed his hemoglobin was dangerously low. His mom was told he would need an emergency blood transfusion, but hours later on July 29, everything changed when they learned he had leukemia. Stacey King turned to Facebook and asked for prayers. Her post went viral.

Leukemia patient Colton King has been in the hospital for the last 25 days. 

"We watched the monitor of his heart rate slowing down of his breathing slowing down, and you just kept seeing the praying and you kept seeing the stats go and we just sat there bawling because it was a direct answer to prayer. Within one hour, his breathing and his heart rate was normal," Stacey King said.

He's spent the last 25 days at St. Joseph's Children's Hospital undergoing chemotherapy and searching for a bone marrow donor for a transplant. The form of cancer he has is so rare his pediatric oncologist has only seen one other case in his 30 years of practice. It means the donor must carry a rare 514 gene. 

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"My husband and I just started bawling because he needed a match to save his life and a sibling match is by far the best results," Stacey King said.

On Wednesday, his sister was in class when she learned she would be that lifeline.

Colton King and sister in hospital bed.

"My parents texted me that I was a match and I was so relieved that I was because that means I can save my brother’s life," Kaylee King said.

For the next two months, he'll undergo intense chemotherapy sometimes up to four hours a day. All of the cancer will have to be removed before he can get the transplant.

"He is resilient. He is brave. He is strong and what's amazing is he's not even complained once through this whole process," Stacey King said.

Until then, Stacey King says she and her family will be leaning on their faith to make it through.