TVSquad

There is something we fans of The O.C. don't talk about: the long, lost sister of Marissa Cooper. Where did Kaitlin go? Remember the little girl who was always in the background during season one? She didn't have very many lines. In season two, she was shipped off to boarding school and gets one mention when Julie Cooper asks for money from her new husband, Caleb Nichol, to buy Kaitlin a new horse. Now that Caleb is dead, Julie Cooper is broke and Kaitlin must return to The O.C. It turns out little sister is a chip off the old block.

FOX cast Willa Holland to play 14-year-old Kaitlin Cooper, who returns to The O.C. during winter break, during a stretch of shows that will air in early 2006. Holland has show biz in her blood--or, at least it surrounds her--because director Brian De Palma is her step-father. Her bio on IMDB says, from 7 to 11 years old, she was the top child model in the United States. Wow. In that picture, she actually kind of looks like she could be Mischa Barton's younger sister.