"The Young and the Restless" originally focused on two core families: the wealthy Brooks family and the working class Foster family. After a series of recasts and departures in the early 1980s, all the original characters except Jill Foster Abbott were written out. Bell replaced them with new core families, the Abbotts and the Williamses. Over the years, other families such as the Newman family, the Barber/Winters family, and the Baldwin-Fishers were introduced. Despite these changes, one of its most enduring storylines was the four-decade feud between Jill Abbott and Katherine Chancellor, the longest rivalry on any American soap opera.