Erin grew up on the Gulf Coast as a competitive swimmer, life guard, swim instructor and waterfront manager. She is an alumnus of UCLA, and began serious diving in Southern California in the late 1970's. She is a Los Angeles County/NAUI instructor-trainer, certified cave-diver and co-owner of the Morgan/O'Neill Underwater Co. This multi-faceted partnership has produced multimedia educational marine life programs, trained all level of divers, photographed and written for several magazines, worked in the film industry doing training, adaptations and stunt work, lectured, conducted worldwide dive-travel tours and contributed to several books. While conducting research on Women in Training (1983) Erin gathered information that sparked her interest in gender-specific dive issues. As a columnist for several dive publications, Erin wrote of these topics, and the collaboration of these became the book she co-wrote with Ella Jean Morgan in 1992, When Women Dive.