Born on 1959 in Vernon, British Columbia, Mills began singing back-up vocals for Canadian bands in the late 1970s, most notably the British Columbia-based band Steelback.
After signing on with the Headpins in 1981, the group began a three-album run at the top of the Canadian charts. Their debut album "Turn It Loud", quickly went platinum and topped the charts for six weeks. It spawned the hit single "Don't It Make Ya Feel". Their follow-up, "Line of Fire", produced the hits "Celebration" and "Just One More Time". The Headpins toured Europe and North America while opening for bands such as KISS, Whitesnake, ZZ Top and Aerosmith, among others.
Mills released her debut solo LP, Never Look Back, backed by the Unsung Heroes.
Darby has been married to her husband Brian Wadsworth since the mid 80s and has 2 sons Clayton and Parker. When not on tour, Mills teaches tae kwon do