She comes from a very wealthy background: her father is a real estate developer who founded The Newport Group, one of the most powerful companies in California. Although the Nichols appear to be the envy of Newport, Kirsten has stated multiple times that she was unhappy with her family life due to her distant and domineering father, alcoholic mother and rebellious sister.

Seth would humorously refer to her no-nonsense persona as "The Kirsten".

When Ryan's biological mother Dawn leaves Newport for good in the first season, she notes that Kirsten personified everything a mother should be.

Like Seth, Ryan, despite his stubborn streak, clearly values her approval and affection. Kirsten appears to be shallow and materialistic like her fellow "Newpsies" but it becomes apparent that she is not one of them and prefers to occupy herself with her work and family; she is often seen grousing privately about the other wives' gossipy attitude prior to parties and social gatherings, which she attends only because of her family's social standing.

Kirsten Cohen (maiden name Nichol) is a fictional character on the FOX television series The O. Kirsten is the wife of Sandy Cohen, mother to Seth Cohen, and the adoptive mother of Ryan Atwood.

Originally portrayed as being unwelcoming towards Ryan in the Cohen household, she began to develop feelings for the brooding teenager, going on to accept him as a central member of her family.

Kirsten Nichol was born in Newport Beach in Orange County, California.She is the eldest daughter of Caleb and Rose Nichol, elder sister of Hailey Nichol, and elder half-sister to Lindsay Gardner. In "The Best Chrismukkah Ever", Seth described her background as "Waspy Mc Wasp".They married, and Kirsten gave birth to a son, Seth. Sea", they celebrated their twentieth anniversary and Sandy serenades her with the song "Don't Give Up on Me".Shortly after Kirsten began her family, her mother became ill with ovarian cancer. She joined her father at The Newport Group, becoming the workaholic she was introduced as at the beginning of the show.In contrast to her husband, who campaigned for Democratic presidential candidate Walter Mondale in 1984, Kirsten was relatively conservative and supported the Republican Party because her parents did.Kirsten herself has admitted to being a stricter parent and has sometimes clashed with Sandy's "hippie parenting".