Christie Brinkley's estranged husband paid his former teenage lover $300,000 to keep quiet

Architect Peter Cook, 49, gave Diana Bianchi the money to remain mum and not take him to court for sexual harassment.

Bianchi and the married Cook began their affair when she was just 18 and had begun working in his office.

"What Cook did is prey on an 18-year-old girl. It's a textbook case of why an employer is not supposed to carry on a relationship with an employee," Bianchi's lawyer Joseph Tacopina has said.

Cook "first physically made advances at me ... probably a month after I started working there," Bianchi, now 21, told the New York Post.

A source close to Cook told PEOPLE, "Peter settled because he wanted to his children left out of it. That's the difference between them – he wants the children left out of it and [Brinkley] wants the kids in it."

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