Wilhelmina's little sister Renee (who's real name was Rhonda) she's somewhat a lot like her sister as both apparently rebel against their father and have changed their names. Renee seemed normal like anyone else, at some point in her college years, she developed a mental illness that affected her moods greatly. When she became invloved with a college professor it affected her so much she instantly believed him to be cheating on her with his secrartary.
She sought out to destroy her competition and attempted to cause a fire to kill his secrartary. However, that planned backfired and he got killed in the fire instead. Its most likely her father covered up the incident. But he had her under go years of therapy, which she was given mediciation that was suppose to keep her moods under control.
She hooked up with Daniel one night at a bar. They had a one night stand, which he woke up at her place, not knowing it was Wilhelmina's. Thinking Renee's in the shower, he goes to surprise only to get a big shock to see Wilhelmina both are shocked and stunned to see one another at her place. Wilhelmina was more than unhappy about the relationship.
Initially, Renee got involved with Daniel just to annoy her big sister, but she and Daniel started to have real feelings for each other and they considered pursuing a relationship. Wilhelmina didn't want anyone to stand in the way of her ambition, not even her own little sister, so she had Marc switch out Renee's mood-stabilizing medication, causing her to have a breakdown that almost resulted in Betty being killed in a fire that Renee started. However, after a calm and desperate talk, Betty convinced her to calm down and see that Betty didn't want Daniel and that he cared deeply about her.
Daniel came in time and saved them both from the fire. Unknown that Wilhelmina was behind it, she took Renee and had her sent to the mental hospital.