Careful, I'm My Sister's Keeper!

A rumour goes round that Zack Anderson is carrying on with a woman from his past. His wife Yvonne has no tolerance for that kind of thing and decides to divorce him. Before she does, she asks her younger sister Shirley what she means to do. Shirley Ryder was taken in by Yvonne's family as a small child and the two grew up as sisters. When Yvonne married Zack, Shirley went after Zack's younger brother Ryan so that she could go on living in the same house as her sister. She got in front of him by staging a collision and playing the injured party, and the marriage that came out of it was a sham that both of them understood as one. Even so, she and Ryan had come to have real feelings for each other, and the feeling was understood on both sides. Her answer to Yvonne comes without a pause: "Yes, divorce. If my sister is divorcing, then I'm through too." Zack's affair turns out to be a misunderstanding, and the two brothers go after their wives to put things right.