10-Year-Old Becomes Lifesaving Hero for His Father

When Dr. Nick Mondek discovered his cancer had returned this spring, he never imagined his 10-year-old son, Stephen, would save his life.

Stephen proves that heroes come in all shapes, sizes, and ages,” Mondek told ABC News. “They may be right in front of us, and one act of courage can completely change your life.”

A Tough Diagnosis

Mondek, a Los Angeles anesthesiologist and father of two, had battled acute myeloid leukemia, a blood cancer, with chemotherapy and a stem cell transplant. In 2022, his older brother, Dave, had donated stem cells to him.

This time, Mondek searched extended family and the National Bone Marrow Registry for a match—but found none.

“It was a dismal prognosis,” he said. “I needed a donor immediately, and there was no one available.”

Acute myeloid leukemia progresses quickly, according to the National Cancer Institute. Standard treatments include chemotherapy, radiation, and stem cell transplants. For Mondek, another transplant became his last option.

Stephen Steps Up

Doctors at Cedars-Sinai successfully extracted stem cells from Stephen. On July 30, Mondek received his second transplant.

The proud father praised his son as a hero. “He never complained once,” Mondek said. “He didn’t wear a cape or leap buildings. Instead, he put on a hospital gown and gave me hope.”

Stephen, who had support from his friends, told KABC, “It feels good because all my friends are proud of me.”

Recovery and Remission

Both father and son are now home. Stephen quickly returned to normal activities. “Within three or four days, he was back at baseball practice,” Mondek said.

Mondek’s recovery shows promising results. “They tested my blood for leukemia DNA last week, and they found nothing,” he said. “I’m still in remission, and there’s no sign of cancer.”