Blood donors typically don’t ever know who receives their blood, only that it gets used. But on Friday, Jeanne O’Callaghan found out that, in 2015, her donation provided a life-saving transfusion for a baby boy.

Nathan Johnson was 4 months old, jaundiced and his stomach distended, when he was rushed to Phoenix Children’s Hospital, his hemoglobin level almost undetectable.

“I felt like I was going to lose my little boy,” said his mother, April Macak, at a luncheon to honor blood drive coordinators for Vitalant, which operates blood donations centers nationwide.

“That first blood transfusion brought him back," she said. "That second blood transfusion kept him here.”

The blood for both those transfusions was O’Callaghan’s.

Since then, Nathan has received blood from more than 80 donors, who have given 1,375 times, range in age from 17 to 80 and live in 25 cities. At the luncheon, Nathan, now 5, met 14 of them, handing each a Valentine's Day card.

“It makes me so happy that I do donate,” O’Callaghan said.

She donated blood for the first time on April 19, 1995, the same day a truck filled with explosives rocked a federal building in Oklahoma City, killing 168 people, including 19 children, and injuring more than 500.

“I’m supposed to be here,” O’Callaghan thought as news of the explosion reached her in the mobile blood center outside her Phoenix office. It was how she could help, and why she kept donating, 54 times since then.

“Thank God for people like that,” said Nathan’s father, Tony Johnson.

Nathan's body produces immature red blood cells, which break apart rapidly. He must receive a unit and a half of A-positive blood every four weeks. He’ll need transfusions for the rest of his life.

Johnson hugged O’Callaghan and told her that during Nathan’s monthly transfusions, they wonder who donated each bag of blood.

“It’s magical seeing everyone,” Johnson said. “They’re honestly a part of him.”

Reach Karina Bland at karina.bland@arizonarepublic.com. Follow her on Facebook and Twitter @KarinaBland.

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