Brother McNeil was born in Inglewood, California and grew up in Ogden, Utah and Placerville, California. He served a mission to Curitiba, Brazil. He was married in the Salt Lake Temple to Rosemary Tenorio and has three sons. He earned his PhD from Brigham Young University in Physics and Astronomy. His dissertation focused on evidence for supermassive Black Holes at the center of galaxies. He enjoys outdoor activities like camping and hiking.