Christie Brinkley's husband spent $4,000 a month on internet porn sites using their 13-year-old son's identity, a court heard yesterday.
The husband, 49-year-old SCUMBAG Peter Cook, also had an affair with a teenage employee, slut Diana Bianchi, below.
Christie Brinkley arrives at court yesterday for the start of her showdown with estranged husband Peter Cook, and his former lover , teen Diana Bianchi
During opening arguments at Central Islip Court on New York's Long Island, Miss Brinkley's lawyer Stephen Cohen said Cook visited websites devoted to sexual swingers - using their son Jack's name.
Jack is Miss Brinkley's son from her third marriage, to property developer Richard Taubman.
Cook, her fourth husband, adopted Jack shortly after they wed in 1996.
Arrogant, smug asshole Peter Cook arrives at New York State Supreme Court
She fought to have the hearing held in public, saying her children needed to know the truth about the break-up.
The couple are battling for custody of Jack and his sister Sailor, ten.
Four-times-married Miss Brinkley also has a 22-year-old daughter, Alexa Rae, from her marriage to Billy Joel, her second husband.
The 54-year-old mother of three - the inspiration for Joel's hit Uptown Girl - intends to bring 44 witnesses in the case.
Her first was 21-year-old Diana Bianchi, whose affair with Cook ended the marriage.
Miss Bianchi was 18 and working as Mr Cook's personal assistant at his architectural practice when the affair happened. He met her in early 2005 when she was 18 and working at a toy store.
Their affair began that March, around the time he hired her.
She was paid a salary of around $10,000 to type magazine articles on to the company's website.
He also left her cash payments in various spots $250 under the rock outside his office, more behind a painting.
Before their relationship ended in late 2005, they had sex in the office a number of times, and at homes in the Hampton's owned by Miss Brinkley.
The fling stunned Long Island society, of which Miss Brinkley is a leading light. She filed for divorce two years ago as it emerged that Cook had paid Miss Bianchi $300,000 'shut-up' money.
Miss Brinkley also intends to call as a witness a married woman who left her husband for Cook and was then dumped by him.
Cook's current girlfriend and an interior designer he briefly dated are also expected to be hauled into court.
At the opening yesterday Mr Cohen called Cook 'a liar, drunk and adulterer' who spent $4000 a month on porn but failed to contribute to household expenses.