Sarah Chalke as Kate Mularkey
While Kate joined her best friend in pursuing a journalism career, she chose to stay behind the camera as a writer and producer. Her path diverges from Tully's when she chooses to quit her job and become a stay-at-home mom, but continues to rely on her other half when a looming divorce and nonstop teen angst throw a wrench in her plans.
Chalke is probably best known for her role as Elliot Reid on Scrubs, but she's stayed booked and busy since the sitcom ended, with recurring roles on Paradise PD, Friends From College, Speechless, and even one episode of Grey's Anatomy, though after costar Heigl had already departed the show. You can also now see her in Eat Wheaties!, a very meta film currently making the festival rounds.