In early 2011, when software engineer Brian Sumner joined Apple to work on Siri, a voice assistant for the iPhone that was still under wraps, the team was struggling to recruit engineers. So after his first months there went well, Mr. Sumner suggested to Siri’s leaders that they hire his brother, Kevin, another infrastructure engineer. After Kevin came aboard that May, colleagues began to jokingly ask Brian Sumner if he had another brother who could work with them.
In fact, he did. And so the youngest Sumner, Michael, joined the same Siri infrastructure team that June, right after graduating from the University of North Carolina in Chapel Hill. All three brothers, who range in age from 27 to the mid-30s, had studied computer science at UNC, about 60 miles south of the rural county where they grew up, near the Virginia border.