Asked if whether she's optimistic she'll get custody of son Jack, 13, and daughter Sailor, 10, the supermodel said, "Oh, yes."
Moments later, her estranged husband Peter Cook arrived, looking subdued and largely ignoring the press horde.
Brinkley is expected to remain on the stand all of Monday as the divorce trial enters its custody phase. Earlier in the day, she revealed in court how she initially told her children that their father would probably not return home.
She said that she broke the news to them shortly after she had confirmed his affair with Diana Bianchi.
"I said sometimes in marriage one person falls out of love. I think Daddy's fallen out of love with me," Brinkley said in a clear voice, adding that she had also discovered some of Cook's Internet porn at this time.
Daughter's Strong ReactionAfter Brinkley broke the news to Jack and Sailor, she says their daughter had an immediate and strong reaction: "Sailor was upset by that and immediately went to call her Dad and give him a piece of her mind for falling out of love with their mother."
Brinkley testified that Cook adopted Jack when the boy was 4. Asked if his biological father, developer Richard Taubman, was ever involved in Jack's rearing, Brinkley testified, "No, never."
Asked later if Peter ever paid for Jack's schooling, Brinkley testified, "I paid for all the children's expenses." She told the court "he never offered to pay for tuition or anything."
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