Karen Lawrence is the wife of Bill Lawrence and the mother of their son Glenn. Their daughter Emma went missing years ago, then a woman suddenly appeared with old abuse injures all over her claiming to be Emma. Originally the family was overjoyed, but Karen grew suspicious.
It was revealed the woman's real name is Britney Taylor, and she was hired by Bill and Glenn to pose as Emma because she wanted a family and the two men of the house wanted to heal Karen's grief. Most of all, they wanted to cover up the fact that Glenn killed Emma in a fit of rage and Bill buried her to cover for his son.
When Karen found out, she was heartbroken, tearfully present at the sentencing of Bill during his final statement. She later filed for divorce. (SVU: "Complicated")