"Maternal Instinct"

Although Christopher Moseley's sleeping arrangements changed, his role in the household did not.

"He was definitely more of an employee than a husband, a servant with bedroom privileges," said Ralph Cipriano, a Philadelphia-based investigative reporter.

Dean MacGuigan hated his new stepfather, and, according to Dominick Dunne, began calling him "Mummy's pet rat." Dean also began spending most of his time in nearby Philadelphia, in the low-rent district, hanging out with junkies and prostitutes and binging on drugs.

Yet despite his self-destructive behavior, Dean managed to find a nice girl. Her name was Linda and she was from a middle-class family in Colorado. She'd worked as a bookkeeper and went by the nickname Rags. Linda fell in love with Dean and saw a bright future for both of them. In 1992, they were married.

Dean, however, could not exorcise his demons. He spent most of his money on drugs while he and his new wife lived in one of his mother's several homes, a 150-year-old mansion called Louviers, located just east of the Brandywine River. Lisa paid all of the couple's expenses.

In 1995, Dean's older brother, Peter, died from an overdose. Linda begged Dean to go into rehab before his addiction killed him too. He refused. She then appealed to his mother. Lisa, who disdained Linda for her common, working-class upbringing, seemed unconcerned. Rehab was a waste of time, she said. Dean was a big boy. He could do what he pleased.

Finally, a year later, Linda persuaded Dean to enter a program. Almost as soon as Dean was gone, though, Lisa showed up at Louviers with her husband in tow. She had a clipboard under her arm and started ticking off a list of family heirlooms she wanted back. Then she dropped a bombshell on Linda. According to Dominick Dunne, who met Linda, Lisa told her, "I want you out of here as soon as possible."

While her son was away getting help for his drug addiction, Lisa was booting his wife out of the couple's home. "She fired her daughter-in-law the way you'd fire a maid," Dominick Dunne said.

But if Lisa Dean had been upset about Linda's intrusion into her family's privileged life in the Brandywine's Chateau Country, she must have been positively apoplectic about what happened next.