No, it wasn't one of the actual cast members who ended up being the star of the show...it was a cast member's mother. Whitney's mom, Patricia, stole our hearts with her daily "medicine" (AKA a gin martini) and the marvelous way in which she delivers criticism about most of Whitney's life decisions.
Jenna made a splash when she appeared on the Charleston social scene, and there were a lot of rumors swirling about where her money came from. That question wasn't exactly answered, but we did learn that she has an older boyfriend with whom she has a long distance relationship. And he may or may not have a private jet.
After assurances on both sides that Kathryn and Whitney only kissed once, Whitney eventually revealed to Thomas at Shep's country home that he in fact did have relations with Kathryn.