Abby was the mother of Valerie Malone. She and her husband, Victor Malone were friends with Jim and Cindy Walsh in Minnesota before they moved to Buffalo, New York. She and Valerie shared an estranged relationship due to the death of Victor, who had molested Valerie. During Abby's first visit to Beverly Hills, she claimed to not know about what Victor did to Valerie. She learned from Tom Miller and Valerie that Valerie had threatened to go to the police on the night Victor was killed. She and Valerie made amends before Abby returned to Buffalo.
Abby returned to Beverly Hills in season 8 to visit Valerie and began a romance with Bill Taylor, despite objections by both Kelly Taylor and Valerie. After Bill proposed to Abby, the wedding day was set, but Bill backed out at the last second, breaking Abby's heart. After Abby showed up in season 9 with fiance Carl Schmidt, it came out that Abby knew what Victor had been doing to Valerie along, but felt that Victor was going to get help. When Valerie found this out, she went out of her way to hurt her mother, sleeping with Carl the night before his and Abby's wedding.
Abby slapped Valerie when she found out about their indiscretion and the fact that Valerie killed Victor after struggling over the gun. Carl later annulled the marriage to Abby and went back to Buffalo alone. Abby prepared to turn Valerie into the police for Victor's murder, but when Abby found out Valerie was going to confess to the murder, Abby stopped her and they moved back to Buffalo together.