Famous for her role as Susan Martin Wyatt Carter on the soap opera Search for Tomorrow and for her portrayal of Holly Laird on the NBC series Fame, Gibb is also notable for her work in the 1986 Oliver Stone film Salvador and for her role as Amanda Bentley in several of the Diagnosis: Murder movies.
In her early teens, she signed with the Eileen Ford Agency and became a cover model for both Young Miss and Vogue magazines.
She received a Golden Globe nomination for her role in the 1993 television movie version of the musical Gypsy.
She was born in Bennington, Vermont and raised in Westport, Connecticut. Before ending in divorce, her marriage to Scott Kramer produced three children.
She made her screen debut in the 1980 Woody Allen film Stardust Memories.