Reeser guest-starred as Olivia Green, the new lawyer in town that takes over for George Tucker (Scott Porter). Just like fellow New Yorker Dr. Zoe Hart (Bilson), she has a hard time adjusting to Bluebell.
While on set in September, Reeser posted an adorable WhoSay photo of the costars reuniting. "Love this girl, such a pleasure to work w/ her again!!" she captioned. "A mini #OC reunion on the finale ep of @CWHartofDixie."
The following month, she also ran into her O.C. onscreen boyfriend Ben McKenzie, who played rugged Ryan Atwood. "All right, OC fans, here ya go," she wrote on Oct. 12. "Backstage at @ThrillingAdv in Brooklyn :) #nyc @ben_mckenzie #TAH #theOC."
Bilson played Summer Roberts on the Josh Schwartz-created teen drama The O.C. After plenty of Sandy Cohen bagel mornings and laundry loads of Ryan's white tank tops, Reeser joined as uptight (and very perky!) Taylor Townsend in the third season.
Bilson and Reeser have both become moms since saying goodbye to Ryan Atwood, Seth Cohen, and the rest of the gang. Us Weekly broke news in November that Bilson welcomed daughter Briar Rose with boyfriend Hayden Christensen. Reeser shares sons Finneus James, 3, and Dashiell Ford, 16 months, with estranged husband Jesse Warren. The Entourage actress filed for divorce in November.