One mother chose to make a serious medical sacrifice to save her 4-year-old son, and she didn’t have to wait long for good karma to come swooping in. Kerri Evensen of Wisconsin was undergoing routine testing for her liver donation to her son when doctors found a critical problem with her own health. During Kerri’s MRI, doctors discovered an aneurysm near her kidney — something she had no prior knowledge or symptoms of.

“The aneurysm could have burst and could have been severely life-threatening,” Tom Evensen, Kerri’s husband, told ABC News.

An aneurysm occurs when a blood vessel expands because of weakness in the vessel. The problem was corrected via surgery, allowing Kerr to be considered once again for donating a portion of liver to her son. “I know I would never have done any other test to find this aneurysm in time,” Kerri told WKOW-TV in Madison. “So he absolutely 100 percent saved my life, by checking… to save his life.”

Her son, Auden, was diagnosed with alpha-1 antitrypsin deficiency, a rare liver disease where the organ fails to create a key enzyme. Because of this, Auden’s blood sugar is often uncontrollable, resulting in an enlarged liver and spleen. He can only play for a couple minutes before developing a fever and “overheating.”

After the previous failed attempt, Kerri will be donating 40 percent of her liver to her son, with doctors scheduling the second attempt for November. According to Tom, the transplant will solve all of Auden’s ailments. “To finally put a date on it is really exciting,” he said.