Jackson Leyden had always been a healthy kid; he practiced taekwondo, and he played lacrosse and baseball. But in 2011, a few months after his eighth birthday, he began having seizures several times a day. Many were brief, a half-minute of staring into space, but he also had severe episodes in which he would collapse, sometimes injuring himself. Over the next two years, he was hospitalized about 50 times, and he missed much of fourth and fifth grade.
His parents took him to more than 20 doctors around the country, and he tried more than a dozen medications. Nothing worked. Two