It's day four in Christie Brinkley and Peter Cook's divorce trial and ET was there as the estranged pair made their way into a Long Island, NY, courthouse. Christie, dressed in a light-colored frock and tan sweater, told the press today she was "feeling fine," today, while Peter, who arrived alone, kept quiet.

Dr. Stephen P. Herman, a forensic and clinical child and adult psychiatrist who has seen both Christie and Peter, as well as their kids, took the stand this morning. He testified that Peter's behavior could've been compulsive and that he would allegedly watch pornography every day, but said there was no evidence that he was a pedophile.

The doc told the court that he believes Christie should get custody of her and Peter's two young children, adding that joint custody is "out of the question" right now, and that it's best for the kids to have one primary residence. However, he suggested that both needed to engage in therapy sessions.

He said Christie needs therapy as "an outlet for her anger and feeling of betrayal," according to the Associated Press.

The psychiatrist also said Peter is a "narcissist" who "needs constant reassurance that he is a terrific guy."

The doctor also addressed Peter's affair with Diana Bianchi, calling it bad judgment on Peter's part. The doctor also suggested the kids remain in treatment.

Christie is back on the stand being cross-examined by Peter's attorney, where she is testifying to what she believes is his addiction not only to sex but also to risk taking in general, including driving fast -- even with the kids in the car.

Keep checking back here for more on Christie and Peter's explosive divorce trial.