A New York mother not only donated a kidney to one of her twin sons, but she also lost 15 pounds to do so, the New York Daily News reported.

Evette Leavy, 44, had been ruled out as a potential donor because she had gestational diabetes while she was pregnant. But the guidance counselor at Intermediate School 318 in Williamsburg, Brooklyn couldn’t bear the thought of her 14-year-old son Brian going on dialysis, so she decided to get in better shape to make herself a better candidate.

Brian and his older twin brother Alan, from Long Island, were diagnosed in 2001 with a rare condition known as focal segmental glomerulosclerosis, which is a wasting kidney disease.

Alan needed a kidney last year when his began to fail. His father Brian De Vale, principal of Williamsburg Public School 257, stepped up and doctors at New York-Presbyterian Hospital Weill Cornell performed the transplant.

One year later, Brian was facing dialysis and a kidney transplant wait list as his condition began to deteriorate.

"I felt panicked," said Leavy, who then decided to make another effort to qualify as a donor.

Laying off junk food and exercising daily helped her lose 15 pounds and pass the rigorous donor tests. She and Brian had the transplant surgery at Weill Cornell on July 22.

"It went like clockwork," said Dr. Sandip Kapur, who operated on Alan last year. "It was a perfect operation and his kidney functioned right away. I've been doing this 14 years, and this is probably the first set of identical twins that I've seen that they both had [focal segmental glomerulosclerosis]. It's very unusual."

If everything goes as well as the operation, Brian’s new kidney could function for 20 years.

"I feel grateful that my mom would work so hard to give me a kidney," he said. "I'm feeling a lot better now."

De Vale admires his wife for putting in the extra effort.

"I just walked in and had the operation," he said. "She had to work to get this done."

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