Is This Scene from "Gone With The Wind" Realistic?

Near the beginning of the movie, Ellen O'Hara comes home after attending Emmy Slattery in childbirth. She found out that the child is the illegitimate offspring of the O'Hara's overseer, Jonas Wilkerson. As a result, she insists that her husband fire Jonas "first thing in the morning," and Gerald reluctantly agrees. In your view, how realistic is the scene? In other words, would a plantation owner really care whether the overseer was playing around on the side? Or is the fact that he got caught is what created the problem? Thanks to all who respond.