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Toddler Meets Life-Saving Bone Marrow Donor

iStock/Thinkstock(PHOENIX) -- When she was 18 months old, Maddie Weimer broke out in red spots all over her belly and back. Weeks later in April 2012, blood tests and a biopsy led to a frightening diagnosis -- Maddie had myelodysplastic syndrome or MDS, the same rare blood disorder that struck ABC's Robin Roberts.

MDS, which can lead to leukemia, is even rarer in children, according to the American Cancer Society.

Maddie's mother Stacey Weimer was told the "only option" for Maddie's survival was a bone marrow transplant. But unlike Roberts, whose sister Sally-Ann was a perfect match, Maddie had no siblings and none of her relatives were compatible.

Now 3 years old, Maddie is in remission thanks to Bailey Personette, who in 2011 volunteered to be a bone marrow donor at a fair held at Purdue University in Indiana. Personette, now 21, said she never hesitated.

"It took about two minutes," she said of the simple mouth swab test that landed her on a donor registry. Eight months later, she was notified there was a baby in need.

"When you get the call that you are a match and this could be lifesaving, for me, without a doubt, I definitely wanted to do this," she told ABC.

Thursday, a year and a half after Maddie's October 2012 bone marrow transplant, she met her donor for the first time at Phoenix Children's Hospital.

"There was never any doubt in my mind that I would meet her," Weimer said of Personette. "She has given my daughter a second chance at life."

Young adults like Personette make up the biggest increase in new bone marrow donors, according to James Kirkland, spokesman for the national donor center Delete Blood Cancer DKMS. 

"They are also the donors most in demand because they are healthier and in a more robust state than any 45-year-old," Kirkland said.

Maddie's doctors told ABC News that Robin Roberts' battle with MDS helped open the doors to new and younger bone marrow donors.

Blood cancer kills more children in the United States than any other disease, according to Delete Blood Cancer. They say that 70% of all patients needing a transplant have to look outside the family for a match, and of the 14,000 Americans who need transplants each year, fewer than half will find one.

At first, Weimer and her husband AJ said they were discouraged because their insurance company did not have a financial contract with the hospital.

But the hospital's transplant program made arrangements for the family to go out of state to Seattle Center Care Alliance at Seattle Children's Hospital, which used the bone marrow donor registry Be the Match.

In July 2012, the family learned that the hospital had found a perfect "10/10 match," which means Maddie's and Personette's human leukocyte antigen or HLA typings were the same, ensuring the best chance of success.

"We didn't know anything except the donor was a 19-year-old female," said Weimer.

In preparation for the transplant, Maddie had eight "vigorous" days of chemotherapy. By October, her immune system was suppressed enough so her body would not reject Personette's bone marrow.

The transplant was quick and simple, and involved an IV infusion of Personette's bone marrow cells into Maddie's vein.

Despite the near-perfect match, Maddie developed graft-versus-host disease, a complication in which the donor cells attack the recipient's body.

"It looked like she had third degree burns from head to toe and fevers over 105 degrees for three days," said Weimer.

Dr. Roberta H. Adams, director of the transplant program at Phoenix Children's in association with the Mayo Clinic of Arizona, said that Maddie's MDS was caused by a genetic deletion on her number 7 chromosome. Because the disorder was genetic in origin, the Weimers said they were worried about having more children. But doctors reassured them the mutation was not hereditary.

"It's a pretty common finding in MDS and one of the flags we look for to help confirm the diagnosis," said Adams. "We suspect it causes the disease. I wouldn't say this family is at increased risk in having another child. It happened in her blood stem cells, not the stem cells in her whole body.”"

While Adams said Maddie "is not completely out of the woods," she also said Maddie "has done very well and we are optimistic about her chances."

By August 2013, Weimer said Maddie was starting "to act more like a fun-going toddler and finally put on weight."

As for Personette, her part of the transplant also went smoothly. Be the Match paid for her flight to Georgetown University Hospital in Washington, D.C. She was put under anesthesia, two six-inch needles were inserted in her lower backbone and the marrow was removed and sent off to Maddie in Seattle.

Personette said she carried a stuffed lamb along every step of the medical journey, taking photos and creating an album she gave to Maddie, so she could feel a part of the process.

Maddie's doctor said she was impressed with the generosity of Personette, who is now a college senior studying nutrition.

"I have been surprised by the number of young people signing up as donors," Adams said. "There has been a real change over the last five years. That may be because there has been a better educational approach at college campuses where younger people congregate. It's an age when young people are very altruistic and want to participate and know about it."

"And it gives you the life-long feeling that you've saved someone's life," Adams said. "Few of us can say that."

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