Andrews was born in Christchurch Women's Hospital at 23:45 on 31 December 1999, fifteen minutes short of the year 2000. Her father is Olympic cyclist Jon Andrews, who represented New Zealand at the 1990 Commonwealth Games and 1992 Summer Olympics. Her mother is Angela Mote-Andrews, who competed internationally in mountain biking. Mote-Andrews was preparing herself for her inaugural participation at world championships—the 1999 UCI Mountain Bike World Championships in Åre, Sweden—when she got pregnant. She has one younger sister, Zoe.